TridacLgtgFAQs

FAQs about Giant Clam Lighting 1

Lighting for 120 gallon reef with clams 8/15/08 I am in the process of setting up a 120 (4' x 12" x 12"). I would like to keep clams. I have been looking at the Nova Extreme T5 lighting fixture with 8x54 W bulbs. Four of them are 10,000 K daylight bulbs, and the other four SlimPaq 460nm Actinic for a total of 432 W. <A nice fixture.> Will this be sufficient lighting to keep clams, and just about anything else in the line of coral that I may want to keep down the road? <Yes and no. It greatly depends on the individual species of clam/coral you wish to keep and where in your tank. Personally, I would swap out two of the actinics for 10000K bulbs. Having two vs. four actinics will not change your look too much. The nice thing about the fluorescent fixtures, T5 included, is that the placement of the actinics can have a huge impact. Placing the actinic bulbs at the front of the fixture will give the look that most want while allowing you to run the balance in daylight bulbs. Even then it will be a bit weak for a Crocea clam near the bottom, half way up or higher will be fine, where such a clam should be anyhow (on the rockwork). For the end all, be all lighting to keep the critter wherever you want I would think about adding a couple more bulbs.> Thank you for your help. Jeff <Welcome, Scott V.>

Re: Lighting for 120 gallon reef with clams 8/15/08 Thanks Scott, <Most welcome.> What do you mean add two more lights? Do you mean two more in addition to the two that you suggested I ad to the fixture to replace two of the actinic lights with a 10,000 daylights? <Yes, if you wish to keep a Crocea or Maxima clam lower on the rockwork. If you wish to keep them in the upper half or third of the tank, switching out some of the actinics for daylights will suffice.> Or, just add two more 10,000 daylights? What I'd be better off with a halide fixture? <No, I am of the "school" that T5s are just as good, the halide advantage is the shimmer it provides. That being said, anyone still needs sufficient wattage, even with T5.> I am trying to get away from halide, as wonderful as it is, for reasons of heat and cost of replacement. <Agreed.> If clams were not a concern, would the Nova Extreme light be fine for corals (most in general)? <Yes, for most with the correct placement. Adding a few more bulbs gives you more placement options. Again, for me, I would stick with the fixture and swap a few bulbs, place livestock where needed.> Thank you for your help. <Welcome.> Best regards, Jeff <Have fun, Scott V.>

Yet another T5 lighting question 6/27/08 Good evening WWM crew. <Hi Jo Anne, Pufferpunk/Jeni here with you tonight.> I wrote a few days ago about my two maxima clams. Just a quick recap: We have had them for approximately 6 weeks. They seem to gape slightly after the lights have been on for about one hour. The tank is 125g Acrylic tank. (60X24X18 if I remember correctly) We currently have 4 80w T5, 2-10 or 11K AquaBlue and 2-Actinic plus. The brand of light is Giesemann. A. Nixon felt the problem was our lighting. Being they were under T5's at the store and from reading about the clams, I learned that although MH is preferred but T5's can work. I believe WWM's recommendation is 4w/gallon of light, which we fall short of. I want to remedy the situation and give these clams a fighting chance. Our tank was originally a FO tank, so it is in a cabinet with a matching wooden hood. My husband decided he wanted a reef tank and we've slowly made changes. I have since become what he calls obsessed with this tank. I am not sure how I could modify this for MH lights economically. I also am not sure I how I can jam at the least 500w of T5's as this would be the minimum to meet the 4w/gallon rule, without starting all over with lighting. (And possibly being served divorce papers) Any ideas? Also I read in Dana Riddle's book that T5's actually have higher PAR than MH. Is that true? If that is the case is can 500w of MH be compared to 500w T5 or PC for that matter. <It is my experience that T5s are just as good as MH. I am a big fan of T5s & keep clams & SPS under them. I do think you need more of them though. You need at least 1 Daylight bulb. I would think with a DIY kit, you should be able to fit several more bulbs under that canopy than 4. I have 6 bulbs over my 90g & probably room for 1 more. Be sure though that each bulb has an individual reflector above it.> One more quick question, I read that keeping the cover over the top of the aquarium also can decrease lighting. I would pull them but I do have a blue tang. I read they can be jumpy. I want to do what is best for my charges. <If you're speaking of a glass cover, then yes, remove it--the canopy should prevent your fish from jumping. Not only will it diffuse the light but it will cause your tank to overheat. You can screen in the open back of your canopy if you wish with nylon screening, although I haven't heard of tangs being common jumpers. Don't forget to dose calcium for the clams. ~PP> Thank you for your time, Jo Anne

Tridacna maxima, light loving? 06/24/2008 Hello Crew, <<Good morning, Andrew today>> I have a question about my 2 maxima clams. <<Sounds good>> They are placed about six inches from the top of the aquarium, as they are bright blue. I read the brighter blue they were the more light they required. <<Well, the blue clams in general need more light, over and above the clams with a brown mantle. Blue mantle clams are mainly found in shallow water and the mantle acts as a kind of light filter for the zooxanthellae>> They look good until after the lights have been on for approximately 1 hour then they begin to gape slightly. My theory was a PH drop, however PH holds and dKH is 10. <<Param.s sound fine>> We have had them for about 6 weeks. They were bought from a LFS after holding them for us for 2 weeks. They had been kept under T5's at the store. They were transported home and acclimated over the course of 1.5 hours or so by slowly adding our water to the bag. We did not quarantine them due to PC lighting in the QT tank. I have ordered Knop's book on giant clams, however I thought you may be able to shed some light until then. I read through Calfo's invertebrate book and on the internet for someone having the same problem. <<Gaping is usually a sign that the clam is trying to tell you that something is not right, sometimes the gaping of a clam can mean that its basically on its last legs. How many watts of lighting do you have on the tank? as you do not state this in the email>> About our tank: Started 12/07 ~6 months old 125g tank, venturi skimmer, 5 powerheads, live rock in tank and sump, ChemiPure, 4 T5's 2 actinic 2 full spectrum, chiller SG 1.024-1.025 Ammonia 0, Nitrite 0, Phosphate 0, PH 8.2-8.3 We are in the process of setting up a refugium in the sump. 10% water changes weekly. Inhabitants: 1 six line wrasse 1 six spot sleeper goby 2 Perculas 1 blue tang 1 neon goby 6 cleaner shrimp 6 turbo snails 6 small hermit crabs 1 Rose BTA 1 finger leather coral 1 small colony of star polyps <<Don't see any real problems with your stock, may have prob.s caused by the cleaner wrasse. For me, I would put this down to a lighting issue. Sometimes, there is not a great lot we can do, but keep a close eye on the coral, and keep pristine water parameters. As another thought, if there are any corals, anemone's near to it, you should consider moving to save the clam being aggravated by neighbours. Please do read more here. http://www.wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm >> Thank you for your time. Your web site has prevented many mistakes. Jo Anne <<Hope the above helps, thanks for the questions. A Nixon>>

Deresa Clam Lighting - 04/10/08 Dear all knowing WWM crew, <<Eric here today… Hardly "all knowing"…but I am learning more every day thanks to my association here at WWM! [grin] >> Your website is very helpful, and I have gotten many answers from it before. <<Ah, good>> I am hoping you can help with this question... <<Will try>> My tank is a 50 gallon reef, 48" long 13" wide 20" high. I have a 29 gallon sump/ fuge and an ASM G-1x skimmer. The tank is primarily LPS, and is lit by a 250-watt PFO HQI with a USHIO 20k bulb. Is this enough light for a Derasa clam? <<The short answer is, yes… But even though Tridacna derasa is considered a lesser light-demanding species, it would benefit from some lighting in the "longer" spectrums not provided by the 20K bulb (i.e. - a lower a bulb with a lower Kelvin rating), in my opinion>> I had 2 65 watt PC actinics running before, but with the 20k, <<A lot of "blue">> I stopped using them. I was thinking of possibly using 50/50s or 10ks instead along with the 250. <> Would this be a good light addition, or am I fine without them? <<The clam will probably fine as is>> What is the best K rating for these clams? <<Lamps in the 10K range probably provide the overall "best" spectrum sampling>> I do have a 14k if that would be better. <<Give it a try and see what the clam thinks>> I appreciate any and all input! Thanks, Jarod <<Happy to share. EricR>>

Maxima Clam lighting and water flow 04/09/2008 Hello Crew, <<G'Morning, Andrew today>> Long time reader first time writer. I have been searching through the multitude of pages and information on the site, but have not found the specific information that I am looking for. I am currently running a 20H with a Rena XP2, Red Sea Wavemaster Pro running two MaxiJet 600's on the reef turbulent setting and a SeaClone 100 skimmer. I follow the GARF.org sites recommendations for supplements and have a good growth of coralline algae. <<Supplements? Which ones?>> In the tank I have assorted button and clove polyps, a bull's-eye mushroom, a devils hand leather , a cabbage leather, a feather duster, a branching torch coral, and an evergreen starburst polyp. I have two false Perculas, two black and white damsels and a yellow tang <<Yellow tang needs a bigger home, at least 75gallon>>. My clean up crew consists of 5 turbo Astrea snails, 5 scarlet hermits, 1 peppermint shrimp and a sand sifting star. I have 15 lbs of Fiji premium live rock from DrsFosterSmith.com arranged in a patch reef arrangement in the center of the tank with a minimum of two inches of clearance from the sides all the way around. The sand bed is 2" deep. I am running 2X65W PC's with 10,000k and Actinic and two blue moon led's. The photoperiod is 8a to 8p actinic, 9:30a to 6:30p white light, and led's all other. <<8 Hours of white light is more than adequate>> The tank has been running for seven months and the polyps have done amazing in spreading and all of the corals have new growth and open fully. I have ordered a maxima from ORA and would like to know where in the tank to place him and if my lighting is sufficient. <<In my opinion, your lighting is not sufficient to support a maxima clam as these are a more light intensive SP. Couple hundred watts of T5 or metal halides are more suited. Placement wise, place on the substrate to start with, while its getting used to a tank for a week, and then moved to a suitable location on the rockwork>> I have read that they do not like a lot of water flow and I want to ensure that it opens up and thrives. <<Clams, as a norm, do not like high flowing tanks, however, the maxima can tolerate this to a certain degree>> Thanks for listening (reading) my long winded dissertation. Dave <<Hope this helps Dave, Good luck in what you chose. A Nixon>>

Clam question, sys./lambda reading 3/12/08 Hi Crew, I need your in opinion as to whether or not I can get a clam. I have a 55 gallon FOWLR system running for almost 2 years now. It is 4 feet long and 18' deep with 1.5 inches of live sand/ <I'd increase the depth here... at least to four inches. See WWM re> aragonite with live rock. The current inhabitants are Magnificent Foxface, <Needs more room> Yellow tang, sleeper goby, cleaner shrimp, 5 Chromis <Ditto> and some turbo snails. We feed them Formula 2 flakes, Hikari frozen brine or mysis everyday and New Life Spectrum Sinking pellets/ Green Marine Algae occasionally. We have a protein skimmer, Fluval 404 for filtration and some powerheads. For lighting, we have Nova Extreme and it has 2 actinics 54 watt and 2 white 10 000k, also 54 watt. We also run 2 Corallife bulbs, one actinic <Switch these actinics out for more white> and one white 10 000k, both 28 watts. <Not enough light intensity for a Tridacnid> Both the Nova Extreme and Corallife run T-5 high output bulbs. The actinic bulbs go on 3 hours before the white ones and run for 7 hours in total simultaneously. We do 15- 20% water change bi-weekly with RO water and Kent sea salt. The salinity is set at 1.024, Ph= 8.4, ammonia is 0 - very low, nitrate=0, nitrite=0, phosphate =0, calcium = 450 ppm, temperature is about 74- 76 degrees Fahrenheit (winter) and 84-88 degrees Fahrenheit (summer). (Chiller is not an option due to budget....we use a fan during the summer) I have done some research and found out that T-5's can be used for clams also, and not only Metal halides, if placed high up on the rock work but want to make sure if it is true. <Marginally> If so, is it possible for our current tank condition to have an addition of either a Crocea or Maxima clam (only these two species found in LFS). If we are able to, do we need to add any other additives/ supplements or food for the clam other than doing water changes and the occasional use of Tropic Marin Bio- Calcium? Does the amount of time the light is on need to be increased? After reading, I am still confused about light acclimation. The clam at the LFS is exposed to metal halides, how do we get it to slowly adapt to t-5s? <Placing high up... in a system with more light than this> Thank you for your time! <Read here: http://wetwebmedia.com/marind5_5.htm the articles, FAQs files on Giant Clams. Bob Fenner>

Tridacna Crocea Lighting 2/5/08 Hey there! <Hello Jaime.> I have just recently bought a Tridacna crocea clam. I have a 40 gallon tank that's is about 14 inches deep. I'm running 2 36" 78 Watt T5HO's (10,000k daylight and 460nm actinic) I was wondering if this is sufficient lighting to keep a Tridacna crocea clam alive and healthy and if so how high up on the rock work should I put him? <You really need more light, perhaps another two or three bulbs in the 10,000K spectrum. I'd move him as close to the existing light as possible. Changing out the actinic for another daylight (10,000K) bulb would help, but will still be insufficient light for this clam.> Thanks for your help! -Jamie <I highly recommend you research all your future livestock wants and desires regarding their suitability/compatibility in your system. For more information on Tridacna clam lighting check out the FAQ's http://wetwebmedia.com/tridaclgtgfaqs.htm. Good luck, Scott V.>

Lighting For 65g Biotope Shallow Reef Clam Tank (But Not "Really" A Biotope… Bummer) - 01/16/08 Hello, <<Hiya Barb!>> I am in pre-setup stages for a 65g (36 x 18 x 24deep, with a brace in the center) biotope shallow reef clam tank. <<Ahh…I love it when aquarists use the "B" word! Can/will make "life" so much easier in the long term>> I am planning on a DSB of approximately 4"-5". <<Very good…and I suggest sugar-fine aragonite for this>> I have had lots of different opinions on lighting. <No doubt, and you're about to get another>> In my tank I would like a variety of clams, and some stony corals; LPS and SPS placed mid to high. <<Mmm, well…so much for the biotope…>> There are some softies I'd like to try on the bottom, <<So, what you really want is a "reef garden" style of tank>> and eventually some clowns paired with a BTA (this is not certain as I know my tank is small and may be cruel for an anemone). <<Yikes! Indeed…and cruel as well to the sessile denizens of this tank if this motile creature decides to go for a stroll>> I am not planning on many fish; a pair of clowns, some pajama cardinals, possibly some Anthias, and down the road if tank conditions mature as hoped, a dragonet and possibly a blue spot Jawfish. <<Well Barb, I think you and I have different ideas of what "not many fish" constitutes for this tank. While this stock list is not excessive (depending on final numbers of Cardinals and Anthiines), it certainly isn't a "light" load for this tank>> Naturally, this is all up for discussion and will probably change as time goes by! :) <<Ah good…let's do bandy back and forth before anything becomes "permanent">> I will have lots of flow, and a 50g sump with a remote 20g-long refugium. <<All "pluses" here. You will also need a good quality skimmer, and some way to provide chemical filtration (canister filter or media reactor of some kind). And while we're talking chemical filtration…while "researching/reading-up on" the other aspects of reef keeping, do a keyword search on our site and read-up on "Allelopathy">> My canopy is 9" high, but the interior has a shelf where the canopy is to be placed on the tank, so the inside height for lighting is 6". <<Hmm, I'm a fan of metal halide for most all marine systems…but this canopy sounds too limiting/would position the lights too close to the water I think. I think overheating will be an issue…and water splashes could easily "do in" the bulbs or if present, constantly coat/obscure the shields (aside from outright failure, broken bulbs can also pose shock or fire hazards…and a broken bulb that is still burning can seriously damage livestock from excessive UV)>> I am happy to drill the top and sides and install fans for cooling, and the back of the canopy is open so other fans could be placed there if necessary. <<Even so…I think you're best going with T5 lighting if you stick with this canopy>> I live in NE Ohio; hot in summer and COLD (Brrrr) in winter. <<Ah yes, luckily winters are shorter and more temperate here in South Carolina>> My house is kept cool in both summer and winter; pretty much 72-73 year round. <> Here are some lighting suggestions I've received from other aquarists and some lighting vendors: 1. 6x39w T5 HO; brand suggested Sunlight Tek retrofit kit, or fixture, with an assortment of blue to white bulbs. <<The T5s are a viable option, though since you wish to keep clams and SPS (Acroporids I assume), I would go with 8 of the 39w lamps…six 10,000K and two Actinic>> 2. Current Outer Orbit 2x250 10k HQI, 4x39w T5 HO, 9 blue/9white lunar lights <<Too much wattage on the halides>> 3. Current Outer Orbit 2x150 10k, HQI, 4x39w T5 HO, same lunar lights <<This would be my first choice of any listed thus far…though I would be inclined to search out a different brand>> 4. Solaris Galileo LED fixture. Not sure how these are being received yet. <<The systems seem promising and expectations are high… Though currently, you'll about have to get a second mortgage to finance one more than a couple feet in length>> Company claims that the things I would like to have will do "great" under the LED's. <<I have heard these clams as well…have even spoken to folks doing some testing re. I do like the functionality/adaptability/flexibility of the units…I'm just not convinced yet that what is currently offered can go "toe-to-toe" with metal halide lighting. Still, if you can afford/want to go with one of these units it will likely suffice. Just do be aware; any one lighting solution is not going to be the "best" solution in a "reef garden" such as you are planning>> Pricey, too, but again company claims the fixture pays for itself in relatively short time. <<Mmm, will still be measured in "years">> I understand the heat involved with MH so I'm not sure my canopy is high enough for this. <<Agreed…and can cause more than heat issues, as explained>> I don't want to damage the life in my tank, my canopy, or my electric bill (not too much anyway :) ). I also like the option of 24hr lighting in one fixture. <<Are we still talking about the LED fixture?>> The T5 lighting option does not leave much room in the canopy to add lunar lighting, as the canopy is hinged halfway through the top...there is 10" available space in front of the hinges, and 10" behind the hinges. <<Should be plenty… The T5s can be mounted individually with individual reflectors…thus allowing you to use the full measure of the canopy lid>> Please offer opinions and suggestions on these different options, and please be happy to add other suggestions as well! <<Have done so [grin]>> Thank you for your time! Barb M. <<Feel free to write back for further clarification/discussion on any of these issues. Regards, Eric Russell>>

Re: Lighting For 65g Biotope Shallow Reef Clam Tank (But Not "Really" A Biotope… Bummer) - 01/18/08 <<Hi Barb…FYI- I've taken the excerpts of my responses you included from our previous exchange and placed them between double asterisks (**)>> **Ahh…I love it when aquarists use the "B" word! Can/will make "life" so much easier in the long term** This is what I thought! <<Yes, but you've strayed to the dark side [grin]. Not that reef-garden tanks can't be kept…the majority of hobbyists do…but putting some thought toward choosing a particular "niche" on the reef to replicate, and limiting livestock selections re can pay big dividends in the long-term>> ** Very good…and I suggest sugar-fine aragonite for this** Yep! Planned for. <Excellent> ** No doubt, and you're about to get another** That's why I wrote! :) <<Hope you found it useful>> **Mmm, well…so much for the biotope…** I'll say the dreaded phrase; "from what I've read". I read about this style of tank in John Tullock's Natural Reef Aquariums; Simplified Approaches to Creating Living Microcosms. <<Hmm, my reference/hobby books are currently packed-up (in the middle of renovations)>> But, as I've just opened the book I see I've mis-stated myself! Oh, geez. <<Oh?>> Well, here goes: It appears I have mixed up my purposes (but you knew that! lol)... this approach is called in the book "An Inshore Aquarium for Clown-fish". <<I still gotta say, I just don't think mixing corals/clams with an anemone is good practice unless the tank is very large (hundreds of gallons) and the other invertebrate life well established (hardened), and the anemone is suitably isolated/separated from the sessile animals…and even then, best left to experienced hobbyists. If you really want to have that "symbiotic" experience…I recommend you study up on the species of anemone you want to keep (some are easier/better suited to captive life than others) and set up a tank just for this…along with a pair of the proper species of Clownfish>> I think with all the studying I'm doing my brain has become very confused. <<Perhaps a quiet moment with a glass of wine is in order…>> Here's what he suggests. Let's see if you agree with the approach: "for a smaller system" he suggests a pairing of tank-raised Amphiprion clarkii clownfish and a Macrodactyla doreensis. <<Good choices…though there are other suitable; and in my opinion more attractive, Clownfishes that can be kept with this anemone>> Other fish he recommends: Mandarin fish- Synchiropus splendidus or Synchiropus picturatus (added after the tank is very mature), <> Six or Four Line Wrasse, <<Do be cautious here, these can become quite the little terror… Definitely the "last" to be added in the stocking order>> Anthias, Cardinals, Damsels, grazing Tangs (obviously I would not have all these fish, but choose from the list). <<Indeed… But this tank is too small for a Tang as well>> Sabellid worms, Giant clams such as Tridacna squamosa, T. gigas, T. crocea, Hippopus hippopus. SPS corals, with careful placement to avoid interaction with the anemone. <<Mmmm…>> No softies to mess with the anemone, <<Wise>> of which there would be one. What do you think? <<Have stated my opinions [grin]. And I still think the SPS and a clam or two would make for a great display…>> **Well Barb, I think you and I have different ideas of what "not many fish" constitutes for this tank. While this stock list is not excessive (depending on final numbers of Cardinals and Anthiines), it certainly isn't a "light" load for this tank** I'm still learning! And, I'm teachable! << Very good, Grasshopper (imagine my best Chinese accent here). Do keep reading/researching your choices re environmental requirements, compatibility, et al… And if/when necessary…you know where to find me>> **Ah good…let's do bandy back and forth before anything becomes "permanent" ** Yes, definitely, lets! <<Cool>> **All "pluses" here. You will also need a good quality skimmer, and some way to provide chemical filtration (canister filter or media reactor of some kind). And while we're talking chemical filtration…while "researching/reading-up on" the other aspects of reef keeping, do a keyword search on our site and read-up on "Allelopathy" ** I have an ASM G2 skimmer with a Sedra 5000 pump. How's that? <<Should do nicely>> I will read up on Allelopathy, which I believe has to do with chemical warfare between corals in tanks? <<Indeed, but more than just corals… Algae, sponges, many types of organisms can/will employ chemical means of defense>> The chemical filtration will help with allelopathy, I presume? <<And more…>> **Hmm, I'm a fan of metal halide for most all marine systems…but this canopy sounds too limiting/would position the lights too close to the water I think. I think overheating will be an issue…and water splashes could easily "do in" the bulbs or if present, constantly coat/obscure the shields (aside from outright failure, broken bulbs can also pose shock or fire hazards…and a broken bulb that is still burning can seriously damage livestock from excessive UV) ** The rests for the canopy could be lowered about 1-1/2in, would that make a difference? <<...? Wouldn't this just place the bulbs even closer to the surface of the water? Or perhaps I have misunderstood>> Or, I could call the LFS and see if they will let me return it for a store credit. <<This would be my first choice>> **Even so…I think you're best going with T5 lighting if you stick with this canopy** Okay. I think I may be inclined to return it or sell it so I can get the most effective lighting for the tank. **Ah yes, luckily winters are shorter and more temperate here in South Carolina** My son lives in NC on Topsail Island. His winters are nice, too! <<Likely a bit cooler this weekend!>> **The T5s are a viable option, though since you wish to keep clams and SPS (Acroporids I assume), I would go with 8 of the 39w lamps…six 10,000K and two Actinic** Okay, gotcha! **Too much wattage on the halides** That's what I figured when this was suggested! 'X'ed off the list. **This would be my first choice of any listed thus far…though I would be inclined to search out a different brand** Can you recommend any brands? <<Hmm, I generally "build my own" from DIY components. I suggest you visit the reef forums (ReefCentral.com/Reefs.org) and query folks there re a quality fixture>> This configuration would be good, though, for the "new" biotope I outlined above? <<Yes>> ** Mmm, will still be measured in "years" ** This is what I figured, and I am NOT considering it. **Agreed…and can cause more than heat issues, as explained** Yes, I understand. <<Ah good>> **Are we still talking about the LED fixture? ** No, the Current USA 2x150 fixture I mentioned above has 24 hour lighting... it was attractive to me for that reason. <> **Should be plenty… The T5s can be mounted individually with individual reflectors…thus allowing you to use the full measure of the canopy lid** Okay, I will look into measurement information this evening. **Have done so [grin]** Yes, you have, Thank you! <<A pleasure>> **Feel free to write back for further clarification/discussion on any of these issues. Regards, Eric Russell** And, this is my reply... Thank you very much, Eric! Barb M. <<Be chatting! EricR>>

R2: Lighting For 65g Biotope Shallow Reef Clam Tank (But Not "Really" A Biotope…Bummer) - 01/19/08 <<Hi Barb!…just like the last…excerpts of my responses you included from our previous exchange placed between double asterisks (**) for clarity (I hope)>> **Yes, but you've strayed to the dark side [grin]. Not that reef-garden tanks can't be kept…the majority of hobbyists do…but putting some thought toward choosing a particular "niche" on the reef to replicate, and limiting livestock selections re can pay big dividends in the long-term** I feel I've been pulled back to The Light. <<Ah! A convert…>> I do want to do the safest thing for the living beings under my care (insert Grasshopper voice here) :) <<Hee-hee! You/your livestock will be better for it in the long term>> **Perhaps a quiet moment with a glass of wine is in order…** A nice Merlot? <<A fine choice…though I've become partial to the fuller-bodied, woody flavor of a good Shiraz>> **Good choices…though there are other suitable; and in my opinion more attractive, Clownfishes that can be kept with this anemone** Please do tell what these other Clownfishes are. <<Listed here, along with a good article on Macrodactyla doreensis… http://www.wetwebmedia.com/macrodoreensis.htm >> **Do be cautious here, these can become quite the little terror… Definitely the "last" to be added in the stocking order** I understand that Wrasses can be troublesome. <<Some species more than others, yes>> I did read they can be helpful in keeping nasties from bothering clams. Is this accurate? <<It is>> Is there another suitable fish that could take the place of said Wrasse? <<It is my opinion that a suitably-sized Halichoeres species would be a better selection for your tank than "any" of the Pseudocheilinus species. A couple of my faves are H. ornatissimus and H. chrysus… Have a look here… http://www.wetwebmedia.com/halichoeresbestart.htm >> **Indeed… But this tank is too small for a Tang as well** Yep, I know that about Tangs; they need way more swimming room than this tank can provide. Wasn't considering. <<Encouraging to know>> **Mmmm…** A murmur of agreement, or disagreement? <<Of concern…re the inclusion/addition of the anemone>> **Wise** Told you I was teachable! <<Ah, putty in my hands [grin]. But seriously, as much as I like my own opinions, do seek out information from other sources as well, and use your own good judgment to make your decisions>> **Have stated my opinions [grin]. And I still think the SPS and a clam or two would make for a great display…** I agree, and it sure makes it more simple to know what my goal is. <<And more simple to research>> I know I will need to wait probably a year (if the tank matures correctly) to actually bring an anemone home. I've read differing opinions; whether to add the clowns to the tank ahead of the anemone, or vice-versa. What would you recommend, and why? <<If you do this (add an anemone), I recommend allowing the Cnidarian to become acclimated/hardened before introducing the clowns as they can be pretty rough on a newly acquired, and therefore stressed, anemone>> Once I have cured my LR and I am ready for a CUC, what makeup of crew would you recommend for my little niche of clownfish land? Are there things you can recommend, or suggest things to stay away from? <<Indeed… Do read-up on our site re "cleanup crews"…but when utilizing a DSB I am partial to the small burrowing and detritus feeding snails such as Cerith and Nassarius species. The smaller Brittle and Serpent stars are very good detritivores, but can become hazardous to smaller fishes if/when they become large…and do avoid the Green Brittle Star altogether (genus Ophiarachna). Many folks also employ supposedly reef-safe crabs ("hermit" or otherwise), but I don't, as I feel they are "too" opportunistic in their feeding habits>> **Very good, Grasshopper (imagine my best Chinese accent here). Do keep reading/researching your choices re environmental requirements, compatibility, et al… And if/when necessary…you know where to find me** Allelopathy is on the study menu for the weekend. <<Excellent my friend>> **And more…** Which I'll learn about this weekend... probably be back with some questions. <<Looking forward to it>> **...? Wouldn't this just place the bulbs even closer to the surface of the water? Or perhaps I have misunderstood** If I lower the ledges in the canopy, it will ride higher on the tank…giving about 7-1/2" for the lights instead of 6". <<Ah, I see now…still marginal for halides I think>> **This would be my first choice** They <<LFS>> will take the canopy back for store credit. However, I've decided to go with T5 lighting retrofits as you suggested to use with the canopy. <<Okay…do fit "as many" bulbs as you can. And keep the addition of bulbs in the short-wave (Actinic) spectrum to the very minimum>> Thanks once again, Eric, for your guidance (said in my best Grasshopper voice) :) Barb M. <<LOL! Quite welcome, Barb! Cheers, Eric Russell>>

Re: New Setup, Clams 1/11/08 Chris, <Hello> Thanks for you help. <Welcome> Would the T5 system allow me to grow giant clams as well? <Depends> If I were to go with MH, would 3x175W be enough or should I go to 3x250W configuration? And finally, for a watt-to-watt comparison, are the T5HO lights more cost effective than MH? Thank you very much. Cheers, John <All I know about clams I got from here, http://www.wetwebmedia.com/ca/volume_4/V4I3/Tridacna/GotTridacna.htm and the related FAQs , this article should help with the lighting choices and livestock placement.> <Chris>

Crocea Lighting 1/9/08 Hello, First off, thank you for answering mine and the thousands of other emails you must get. <Hello, it is a collaborative effort, we do answer quite a few queries.> I have a 125 gallon tank with an attached 30 gallon refugium & 20 gallon sump. One half of the tank I keep open swimming space and the other half I have live rock. Currently I have two 72 in blue actinic bulbs powered by an Ice Cap 660 ballast. I also have a 36 in PC 10k bulb over the LR. I received a Crocea clam recently and would like to upgrade the PC lighting to MH. <Good idea.> The tank is 18 inches deep, but I plan to keep the clam about 6 to 8 inches from the surface after acclimation to the new lights. Would you recommend 175 or 250 watts for this distance? <The 175 will work fine at this distance for the clam.> Also, what type of corals would you recommend keeping with the clam? <This depends greatly on your taste in corals! Anemones are not a good idea. With other corals just be sure to give the clam its space, and that your corals do not shade the clam. Certain corals lend themselves to be kept with clams, such as Acroporas, simply because they have similar needs in tank conditions (high lighting and flow needs). Thank you <Welcome, Scott V.>

Re: Crocea Lighting 1/10/08 My apologies. The question I wanted to ask is, what spectrum bulb will most benefit the clam? <No apologies, it is the nature of computers. As for bulb spectrum for clams a 10K bulb is far and away considered the best choice. The higher Kelvin bulbs do not provide as much "usable" light for the clam and the lower Kelvin bulbs (6500's) tend to be too yellow for most people's taste. Much info on this is in the FAQ's as well as the link below. Good luck, Scott V.> http://ClamsDirect.com/ Thank you

Loss of powder brown tang 12/26/07 Hello, First off I want to thank you for putting together such an informative site. I have a 125 gallon tank with an attached 30 gallon refugium and a 20 gallon sump. I have about 175 lbs of LR throughout. DSBs are utilized in the display tank and refugium. Specific gravity kept at 1.024 and temperature at 75 degrees. Inhabitants included: 1 Powder Brown Tang, 1 Tiger Wardii Goby, 1 Orange Spotted Goby, 1 Crocea Clam, 1 Skunk Cleaner Shrimp, & 1 Peppermint Shrimp. My heater stopped operating yesterday and being that it was Christmas, I was not able to purchase another. <Yikes, a back up unit next time?> It was cold last night for Arizona standards and the temperature in the tank must have dropped into the sixties. I woke this morning and found the tang dead. I checked the water parameters and everything checked out fine. Do you think it was the drop in temp that killed him? <Sounds likely.> I added the clam a few days ago and it has periodically excreted something from its spout, but I was leaning more towards the temp drop. Also I was wondering, I have two 6 ft blue actinic bulbs running off an Ice Cap 660 ballast. Do you think this will be sufficient lighting for a Crocea clam if I place it near the top of the tank? <No, not enough light and wrong spectrum.> Would it make a difference if I replaced one of the bulbs with a 50/50 daylight bulb? <Very little, you simply will need more light for the clam. Read more on their needs, start here and related FAQ's http://wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm Thank you for your time <Welcome, good luck, Scott V.>
Re: Loss of Powder Brown Tang 12/27/07 Thank you for your quick response. I went out and bought a digital heater and a back up. <Good.> As for my question concerning lighting for the Crocea clam, would it be advisable to run metal halide lamps using the Ice Cap 660 ballast? <Halides would be good, but not on that ballast. You will need the ballast rated for the wattage and type, single or double (HQI) ended, you intend to run. Take a look at different Etailers and the ballasts sold for particular types of bulbs. Hope this helps, Scott V.>

Tridacna Crocea in a Nano 10/12/07 Hi guys, love the site. I'm planning a 29 gallon Oceanic BioCube for my new bedroom and I was thinking about adding a Tridacna Crocea clam. I know the light in the tank is not enough for this clam. But because the size and beauty of this clam I want one. I have found this site that customizes BioCube and could add 2 more 36 power compacts. This would give the system 144w and just under 5 watts per gallon. If I keep the crocea close enough to the top will it live happily? Thanks. <This lighting should work out... but I do have concerns re keeping your water quality up and stable here. Have you read much re the captive care of Tridacnids? Bob Fenner>

Unhappy Tridacna squamosa...Too Much Light Too Fast? - 05/09/07 Hello, <<Howdy>> I purchased a 5 year old Squamosa (about 6-inches) approx 7 days ago. I did a two-hour drip and it acclimated very well for the first day. The second & third day it didn't want to open much, so on the fourth day I gently nestled a rock under it so it could foot hold. Almost immediately it opened up beautifully for about two days. Now yesterday and today it is gaping on and off and the interior of the clam seems sunken in. <<Mmm...>> It is open and the mantel is out and the clam is very responsive. <<A good sign>> Also the color looks good. Is it doomed or can I do anything? <<There is usually little we as hobbyists can do for these creatures once they show signs of decline, but if the decline is attributable to an environmental situation that can be identified and corrected the clam may pull through if not too damaged/too far gone>> It was raised under VHO lights and is now is in a 75 gallon with 2 250-watt metal halides. <Ah! A definite clue... If the clam was not acclimated to the more intense lighting it is likely suffering from photo-shock. You can try shading the clam a bit with layers of fiberglass window screen or the like (have a read here and beyond for more info: http://www.wetwebmedia.com/acclimcoralslight.htm), removing a layer every couple days to allow the clam to become accustomed to the new lighting...though since it has been more than a week since the clam was placed under the halides, this strategy may now be a moot point>> Ammonia 0 Nitrite 0 Nitrate <5 Phosphates 0 PH 8.4 SG 1.024. I have a lot of sensitive corals like Alveopora and a Crocea and Maxima and they are well so I don't believe it is the water. <<Then is likely the lighting>> Its bottom dwelling neighbors are a 3 plate Fungia about 3-5 inches away and the other side a Lobo about 4 inches away. Any help would be great. <<Do also have a read of this article by Barry Neigut of Clams Direct on selection and placement of Tridacnid clams (http://www.wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm ). Regards, EricR>>

Giant Clams and Color Temperature - 08/31/06 Hello Crew, <<Vince>> I have a 150 gallon established reef with mainly LPS and some fish. <<Ok>> I am considering adding a clam and read they do best under 10,000K lighting. <<Not an absolute...but is a good baseline>> My current setup consists of 2 250w 14,000k MH with 2 T5 Actinic. <<This would be fine. I have three T. crocea under a 250w 14000K pendant on the substrate in 24" of water (30" deep tank) they are doing marvelous...I don't want to downplay its importance, but it is not always "all about the light">> If I switch to the 10,000k bulbs do I need to acclimate my current livestock to the temperature change? <<Maybe...depending on the PAR output/age of the bulbs>> My current bulbs are only 4 months old. Thanks for your time, Vince <<To be quite honest Vince, I think your lighting will be fine for "any" of the commonly available Tridacnid species. Placement up/down the water column can be adjusted to suit the differing lighting requirements, though I suspect this to be of little concern. No need to change the color temperature of your bulbs unless it's for "your" benefit...in my opinion>>

Clams/Lighting 6/26/06 Dear Crew, <Stephen> I am 6 months into my first tank. I am pleased to say that with this web sites help and a lot of reading, it has passed with very positive results and no major issues. <Good to hear.> I have one question for you though. I have a 50 gallon tank, it is 13" to the sand bed. At the weekend I upgraded from fluorescent to MH. I have one 150w fitting rated at 20,000K. I had hoped to get a Tridacnid clam in some weeks or months time, I figured that the clam would do OK at that depth under 150W. Now, after reading more of your site, I am worried about the "temperature" of the lamp. Is my set up OK or do I need to change to 10,000k. I live in Japan and I had asked for 10,000 and they persuaded me to buy 20,000. I am annoyed now. <Don't be annoyed. Barry and Sherry Neigut of Clams Direct, use anywhere from 10 to 20K in their systems.> Many thanks in advance. <You're welcome. James (Salty Dog)> Stephen Marks

Clams/Lighting FYI ... more bad code, info. 6/28/06 Crew I recently answered a query re above. Talked to Barry at Clams Direct on this for future reference, and he feels 5.5-10K is ideal for good clam growth. Regards, James

Clams/Lighting FYI ... more bad code, info.ï¿½ï¿½ 6/28/06 <Mmm, do you see any prob.s?> Crew I recently answered a query re above. Talked to Barry at Clams Direct on this for future reference, and he feels 5.5-10K is ideal for good clam growth. Regards, James Bob, Don't know exactly what you meant byï¿½ "more bad code, info". Reason I contacted Barryï¿½was because there were photos on his site that he indicated were taken under 10-20K lighting. I just wanted his recommendation onï¿½what he feels is the best Kelvin temperature for clams. <It took minutes to fix the code... the info. is in direct conflict with your resp. of two days prev.> Regards, James
Re: FYI Clam Lighting Exactly, I didn't feel quite comfortable with the answer after I sent it, which is why I contacted Barry at Clams Direct. Although not entirely wrong, as clams will thrive under higher Kelvin temperatures, just not ideal for anything higher than 10K. I do strive to be correct in my answers. Many times I will search for info other than WWM to ensure correctness. I'm getting there Bob, not perfect or will ever be, but getting there. Soon, I will be the apple of your eye. HA!:) Sorry for the trouble. Regards, James <Will post this more complete input. B>

- Crocea Clam Lighting and Quarantine 6/16/06 - Hi Crew, I looked through the FAQs on clams and lighting, but want to get a personalized opinion in this case, as they seem to vary a bit. I have a 12 gal NanoCube DX for my quarantine tank. It's got two 24W 50/50 PC lights, and I put in a colonized sponge filter, carbon, and a poly-filter. I plan to add a 3-4in T. crocea clam as its first inhabitant, which will then be moved to my display tank. I want to make sure the lighting and filtration in the quarantine is sufficient for such a clam. <The lighting is not... but if the clam is only passing through, then it really won't matter so much.> My intent was to elevate it so to be closer to the light, since they are not terribly bright. <Or strong/intense.> My display tank is 58gal with a 400W 20k MH. Will I have to photoacclimate the clam upon moving it to the display? <It won't hurt, but clams, unlike corals can close almost completely to get a break if they need it.> Thanks for any advice! Jason <Cheers, J -- >

Metal Halide, Shallow Tank, and Clams - 06/12/06 Hello, hope ya'll are having a fine morning. <<Mmm, yes...for a Monday>> Just got back from my bachelor party so I can't complain. <> Anyway, there is a lot of advice out there as far as the appropriate wattage/mounting depth to correlate with certain tank depths, but I can't seem to find any that fit well enough with my situation. <<Much left to personal opinion/subjective interpretation>> Currently I have a 250W double-ended HQI MH lamp with 14k bulb. My aquarium is a 40g flat-back hex with a depth of about 20" from top to bottom. After accounting for substrate and unused space, the greatest depth any of my charges can be possibly kept is 16". <<Okay>> My lamp is mounted approximately 8.5" away from the water surface. <<If your corals are acclimated to this lighting then this is fine. But considering the wattage of the bulb/depth of the tank you could easily move it up several inches...in my opinion>> With the use of a fan heat is kept within sane values (78 degrees). <<Much to be said for evaporative cooling>> I'm worried though that this might be too much light. <<Depends on what you are trying to keep>> My coral charges seem fine and quite happy with the new arrangement. <<Then likely nothing to worry about>> My T. crocea (which I received shortly after) did expel some zooxanthellae right off even though it was placed in the bottom of the tank, <<More likely due to shipping/handling stress, than lighting>> currently it seems fine (mantle spread, not gaping) and I have had it a week now. My main concern is for my smaller juvenile T. maxima (w/ darker gold coloration). <<Any Tridacnid species under 2" is problematic (seem to be especially susceptible to shipping stress/problems with acclimation)...best to obtain these clams at 3"-4" in size for the best chance at keeping them alive>> Is my concern misplaced, as these are light loving creatures, or should I consider raising the lamp considering the depth of my tank? <<What is the clam telling you? If it seems happy and healthy then leave as is. But I also think raising the light a bit won't "hurt" anything if you should so choose>> The T. maxima seems to be happier on the whole since I have started using a sodium nitrate solution. It concerns me though that no matter how much I add I still seem to have 0 nitrates. <<Likely used/removed very quickly...be sure to make increases in small increments...and keep a sharp eye out for the start/increased growth of nuisance algae>> Could this solution be taken out by a skimmer or PolyBioMarine's Poly-Filter? <<Yes>> It doesn't seem likely, being a salt, but my knowledge in that area is pretty limited. I'll appreciate any knowledge you wish to pass my way. If perhaps I have missed this information in your faq, I apologize. <<No worries mate>> Thanks for your help! James Tanis <<Cheers, Eric Russell>>

New Lighting For Clam - 03/15/06 Hi, guys! <<Don't forget the "gals" here too!>> I always hate to bother you guys but I've done quite a bit of surfing and FAQ searching and, although I think I know which way I should go, just wanted to get a final referral before I change my lighting. <<No worries mate...shoot.>> I currently have 2-96watt compacts for a 55 gallon 48x14x19 tank. I was thinking of upgrading to a 4-96watt fixture to double my watts in hopes of it being enough light to sustain a T. squamosa? <> I have mostly polyps and soft coral. What do you guys think? <<Worth trying/doing in my opinion. For the clam's sake my suggestion for lamp type is four 10,000K bulbs. If you "must" have some actinic (would be for you...not necessary for the animals), then no more than one actinic lamp.>> Thanks again for your time, you guys rule! Sincerely, John Kelley <<Regards, EricR>>

Clams and Overflow box question? 2/17/06 Good morning to you- I love this site and have been using it faithfully for a year. But alas... I now need to ask a few questions. I have had a 38 gal. tank for over a year. I am now getting ready to build a 135 gal. 72L x 24W x 18H w/ a plenum and 3 in. LS, 155 lb. LR, 2000 gal. an hour filtration. I have been reading all the articles on Clams and Lighting in reference to water depth, among others. But I am not sure I can do what I am thinking (I may have missed something). I would like to know if w/ a 520w Compact light (6700K/10000k, 420/460nm) in 14 in. of water depth if a Tridacna Crocea would be happy and healthy or would I need to still have a MH? <Should work> Next... I am planning on putting the skimmer box in my tank like in Anthony's diagram. I am putting in 4 bulkheads 1.5 in. ea., the box will be 48 in.'s long centered. I want to leave the sides open for water flow from the manifold around the top. Is this enough bulkheads for the 2000 gal. rate of flow I want to get? <Should be, yes... If it were me/mine, I'd make two (the outside ones), 2" ID, put the bottoms near the same level as the 1 1/2"s> And will I get my flow rate if I use y connecters and plumb 2 an 2 together or should they be plumbed separately for better flow? <Can be linked together... need (likely) to be aspirated to speed flow, reduce noise and "bubbliness"> Thank You for your time-Deanna- <And you for your sharing. Bob Fenner>

Clam Lighting & Placement - 12/17/05 Hello again! <<Howdy!>> Just had one other quick question I was hoping the crew at Wet Web could answer. <> Is a Coralife Aqualight Pro 1-150 watt HQI/ 2-65 watt compact actinic fluorescents/lunar light fixture adequate lighting to do SPS and clams? I have 46 gallon tank, 18 inches deep w/ mounting legs 4-5inches above tank. <<Should be fine.>> If so, could a clam on two inches of substrate in full light thrive or does it need to be higher up? <<This lighting would be fine for a clam at this depth.>> Thanks again for any help you can give. This subject proves to be quite confusing. Thanks, J-Man <<Maybe this will help: http://www.wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm >> <<Regards, EricR>>

Lighting Upgrade for Tridacnids 12/12/05 Hi, <Hello.> Thanks for having this website, it has increased my knowledge of how to properly take care of my tank. <Thank you, I'm glad we have helped.> I just wanted to ask you for a recommendation/suggestion as to this question. <Sure.> I currently have some Shrooms, hammer coral, frogspawn, xenia, and a Monti cap in my tank which is approx. 15inches deep. My question is I currently have A 4X65 (260 WATTS) PC and want to get one crocea clam? <Do you? This clam is the most light loving and sensitive of the Tridacnids so I would research thoroughly, WWM is a good place to start, and the book Reef Invertebrates has a great clam chapter, Giant Clams by Daniel Knop is another great book.> Can I get rid of the PC's altogether and just get two (2) MH pendants. <Yes that would be a great upgrade to keep this clam.> Also, what bulb should I use? My tank is 4 feet in length. <If it were me I would use x2, 250 watt HQI pendants (PFO brand with the electronic ballast) and 10,000K bulbs. That would give you plenty of light.> Thanks again, <No problem.> Jose Nunez <Adam J.>

T. crocea Lighting and Placement 11/30/05 Hi, <Hi Dustin.> I have read though most of your articles and learned a ton of information for when I set up my next tank, but in the meantime, I have a few questions that I could not find answers to. <Ok.> I would like to purchase a T. Crocea Clam (~1-2"), and have a question about the lighting. I currently have a 40g tank, that is 36"x18" x 12" deep, with a 175w 14000k MH light 5" from the surface of the water, along with 3 - 24w 6500k mini-PC's, and a 65w 50/50 ( ? 10000K, ? Actinic) PC. The MH is in the back-right side of the tank, the 3 mini-PCs are in the back-left side, and the PC is along the front of the tank. I leave the MH and mini-PCs on for 11 hours a day, and the PC on for 15.5 hours a day. I currently have 2 hammer frags under the MH and 4 candy coral frags under the mini-PCs. The hammers open up more than they did at my LFS, and the candy coral seems to be doing OK, although the heads aren't opening as much. My questions are: 1) Is 14000k MH okay for a T. Crocea clam, or should I buy a 10000k replacement bulb? 2) Where would the best placement for this clam be (which area of the tank, and at what elevation)? I would be inclined to say at mid-depth under the MH, but I hear they need a more full spectrum (mixture of my bulbs). <I would place it in the rockwork, upper ? of the tank as close to the MH bulb as possible. T. Crocea is the most light demanding of Tridacnids. Also as far as spectrum, most animals hosting zooxanthellae prefer Kelvin ratings of 6,500K to 10,000K. Actinics and bulbs in the 15,000K to 20,000K are mainly for aesthetics.> 3) Is my MH lights left on too long (11 hr/day) for this clam? (I read here that some people leave theirs on for 6-8 hours per day) <11 hours is a bit long, I won't say that it will hurt the clam but it is unnecessary.> <<Where did these clams evolve? The equatorial tropics. Anyone know what the photoperiod of equatorial regions is? 12 hours of light, 12 of dark. The goal is to mimic natural conditions. Marina>><Mmm, gets "dark" much quicker underwater than above... due to angles of refraction, and reflection. RMF> 4) What lighting is best for the candy coral? I have read that they do not like direct MH lighting, so I placed them under the mini-PCs, IYO, what is best? <There placement as far as lighting needs appears fine.> Thanks, and keep up the good work <You are welcome and thank you.> Dustin <Adam J.>

Tridacnid Lighting and Small Water Volumes Hello, I love your site and how detailed it is. <Hello and thank you.> I am planning on putting a 24 gallon cube tank in my office. I was hoping to add maybe one or two light intensive animals a bubble tip anemone or a lower light clam. <Well as I'm sure you know maintaining either in such a small water volume is going to be a difficult task. I would leave out the anemone as most will grow to large for this tank as well as harm/sting other sessile invertebrates like your proposed clam. As far as lower light clams, all that fall into that category (that are readily available), T. squamosa, T. derasa, T. hippopus all get well over 12" in length.> When they get bigger I was planning to move them to my larger 55gal <Ok that would work.> but in the mean time I'm trying to determine what is my best lighting course of action. Stock the cube comes with 32w daylight and 32w actinic PCs, obviously this will need upgrading. My current choices are between adding an additional 64w of daylight PCs or a 70w HQI probably at 14,000k. Are either of these choices acceptable for these critters growth? <Either will be acceptable for juv. Clams of the species listed however a few other concerns should be adjusted. Both of these lighting systems will significantly increase the heat on the system and thus the evaporation. So daily or automatic top-off should be a priority. Tridacnids also need a very stable environment so bi-weekly water changes to combat dropping calcium levels and raising nutrient levels are a must.> The PC is the cheap option the MH significantly more and I don't know that a 70w fixture is strong enough anyway. Any thoughts? <70 watts of MH is strong enough and the bulb life is significantly longer but they will add even more heat than the PC's….in short you can make either work but it will take discipline.> Derek <Adam J.> Washington, DC <SoCal.>

Lighting Up A Clam, WWM Counselors - 11/16/05 Dear FAQ Crew, <<Howdy>> We have a 75 gallon tank, 48 L X 18 H x 18 D with a Coralife Lunar Aqualight 2x 10,000K/65 Watt Compact Fluorescents + 2x 65 watt Actinic bulbs. I think that figures out to about 3.4 watts per gallon. <<Don't get hung up on this method of figuring/computing lighting, is of little value in my opinion. You must take in to account the type (fluorescent vs. single point source), distance from the water , water clarity, etc..>> We want to add a Tridacnid clam and have read varying opinions on lighting. <<ok>> Some suggest that a clam in the top of our 18" deep tank would do okay with our present lighting while others insist metal halide lighting is absolutely required. <<Both arguments have merit, and again, depend on certain conditions/aspects being met. If you have T. derasa then your present lighting is likely fine if you place the clam in the upper half of the tank...if you have T. crocea then I recommend upgrading to the MH lighting. I have seen T. crocea adapt/survive with less lighting, but I wouldn't recommend it.>> We intend to upgrade in a couple of months (January 2006) to the Coralife 48" 2 x 150 w HQI + 2x 96 W actinic + 3 blue moonlight LEDs , but do we need to upgrade before introducing the clam to the main tank (Presently he/it is in quarantine enjoying a metal halide clip on light and growing at a phenomenal rate--almost 3/8" of new shell in a month!)? <<Mmm...considering this, let's wait for January and the lighting upgrade...not all that far off anyway.>> We won't move him to the main tank until we have appropriate lighting. Do you think we can place our clam high in the tank with our existing light for a month or two without the halide lighting or do we need to upgrade the light before we move him? <> Thanks in advance for your counsel. Kathy <<A pleasure to assist, EricR>>

Tridacnid Lighting 9/24/05 Hello everyone, <Hello Tyler, Adam J with you.> I currently have a 135 gallon reef with mostly LPS, Mushrooms & Zoanthids. My tank has 420 watts of VHO lighting. I am planning to upgrade to 760 watts of VHO lighting. Is there any type of clam I could keep with this setup? < A few actually, the two larger clams in the Tridacnid family (T. squamosa and T. derasa) should be fine in your set-up as they are the most tolerant as far as lighting (Compared to their smaller cousins T. crocea and T. maxima). Just make sure to keep Calc. Levels high (350+). Another thing to keep in mind with these clams is their sizes. T. squamosa tops out at around 12" with T. derasa at around 24". See here for more detail http://www.wetwebmedia.com/tridacnidart.htm . Hippopus hippopus would be a good choice too, requirements are about the same but I find the Tridacnids to be more eye catching.> Thanks. Tyler <Glad to have helped. Adam J.>

Re: Tridacnid Lighting round 2 9/24/05 Wow, that was a fast response. Could I keep a Crocea if it was in the upper part of the tank? <I would rather you try a Squamosa or a Derasa first (especially if you have never kept Tridacnids before). The T. crocea is in my experience the most demanding Tridacnid as far as lightning goes and the most finicky as far as water quality goes. Some clam enthusiasts will only recommend keeping these critters under Metal Halide lighting, I won't go that far but I will say I have seen the best success with these under MH. Many of the Croceas sold as "ULTRA" may not hold their color under the intensity of VHO, if you wish to try it, is to place the clam in the upper 1/3 of the tank and monitor it for signs of bleaching, browning and gaping. If you see these symptoms its care is lacking in some area.> Is 760 watts overkill? <Depends on what type of light and targeted specimens (not enough for some too much for others), but for what your keeping this wattage of VHO should be sufficient and then some.> Tyler <Adam J.>

Tridacna Clams And PC Lights - 08/23/05 Hello crew, <<Howdy>> I have been looking into getting some Tridacna clams for my aquarium but I have a two questions. First, I have a 75 gallon tank (18H, 18W, 48L) w/ 8 65 watt PC lights (4 actinic & 4 WT day) and 8 LED moonlights. Is this enough light to keep Tridacna clams healthy? <<Tis possible...but I would recommend either ALL daylight bulbs (6500K or 10000K...your choice), or; if you must have blue lighting, no more than 2 Actinic bulbs with 6 daylight bulbs.>> I know metal halide lights are best but with all the money I put into the lights I have right now, I'd rather not have to go get new lights. <<Keep the bulbs "fresh" and close to the water's surface, and go with T. derasa and/or T. maxima and they'll likely do fine.>> Second question, I currently have a brittle starfish in my tank and I have heard that they eat clams. Is this true? <<Not in my experience/estimation. I have always kept Brittlestars in conjunction with clams...I've never seen nor heard of a Brittlestar attacking a "healthy" Tridacna clam...any perceived predation was likely a result of the star "cleaning up" on an already doomed specimen.>> Thanks
<<Regards, EricR>>

Tridacnid clams need intense lighting 8/5/05 Hello Crew, Dr. E here.<<Hello Ethan, Ted on this end>> Thanks again for the help. This is a quick one....I have 2 Tridacnid clams, I have 130W daylight and 130W actinic light is this adequate?<<Probably not.>> I have looked all over the site and haven't found a good answer concerning actinic lights and clams.<<Tridacnid clams need intense lighting. It is possible to keep Tridacnid clams under PC lighting by keeping the clams closer to the light source (place them higher on your reef) and/or compensating for the lack of light by feeding. However, in my opinion, you are better off upgrading to metal halide lighting. It gives you more options with respect to placement of the clams as well as the option of adding SPS corals to your system.>> Thank you. Ethan H. Morris DVM
<<Cheers - Ted>>

Re: Clams and Upgrading PC Lighting 8/6/05 Thanks for the response. I am not sure what is available to me so that I can use metal halide lighting with the setup I have. I have a Current Dual Lamp light. Do they make bulbs to replace the actinic and day light I currently have? If they do which one do I replace?<<You're welcome. MH lighting and PC lighting use different ballasts and fixtures so that simply replacing bulbs is not an option. You will need to research MH lighting and determine what is suitable for your tank. Considerations include the dimensions of your tank, what livestock you currently have and what you would like to add, hardware aesthetics (using a canopy vs. pendants vs. fixtures). Also, you will need to determine what MH bulb(s) you want to use. My friend, you have a lot of reading! The good news is that WWM has a lot of information to offer.>> If they don't make a metal halide bulb how do you suggest I add one (I have enclosed a photo of my tank). Would adding a halide light be too much for my corals?<<After determining what MH fixture, bulbs, etc. you are going to use, please search WWM on "acclimating corals to MH lighting" and read through the FAQs. Good luck - Ted>>

Re: Clams and Upgrading PC Lighting 8/11/05 Hello Crew, <<Hello again Ethan. Ted here once again>> Thanks again for the response. <<You're welcome>> I am going to add a metal halide light to my system. I have 120g with 130W actinic and 130 Daylight, would adding 175W of Metal halide be too much? Or do I replace my current lights? <<If your 120g tank is the standard dimensions of 48x24x24, then the 175W MH lighting will work fine.>> Thank you.
Dr. E
<<Cheers - Ted>>

Re: Clams and Upgrading PC Lighting 8/12/05 Sorry just to be clear is that 175MH + my current lights or the MH alone?<<Sorry for the confusion. The current lighting (130w PC actinic and 130w PC daylight) together with the new lighting (175w MH) will work fine.>> Ethan
<<Cheers - Ted>>

Clams, lights, Feedings - 7/31/05 Hi <Hi Steve, Ali here...> I was reading you site about T. Clams and got mixed information about lighting and feeding T. Clams. Here's my question can an adult T. Maxima survive and thrive in a 60 aquarium with 260 watts of PC lighting. <That won't cut it Steve, you need halides, preferably 2 x 250watt bulbs. P.C. just aren't intense enough to keep the clam happy long-term.> My second question is do T. Clams over 5 inches still need to be feed live phytoplankton, My last is question will a T. Clam eat copepods and such. <No and no. Intense lighting along with stable (moderate-high) calcium/Alk. parameters will be enough to keep him healthy and growing> Sorry about all the questions but I really want one but don't want it to die a few days later. Thanks <Good luck and keep reading Steve! - Ali>

Lighting for maxima Dear WWM Crew, Let me begin by thanking you for this wonderful site! <Thank you> I have a 29 gallon glass tank with approximately 25 lbs. of LR, a clown goby, an ocellaris clown, a cleaner shrimp, several dwarf hermits, and a mandarin. PH is at 8.2, ammonia is almost zero, same for nitrites, and my nitrates are pretty low. Calcium is about 440 (I'm trying to encourage coralline algae, it's been spreading well lately). I have wanted to keep a Tridacnid for some time now, preferably a blue/purple maxima. I really don't have the money for a metal halide setup, and I've heard that it's possible to keep them under PC's, as long as they're higher up in the tank. Could you give me your feelings and suggestions on this? Thanks so much for all of your time and effort. This site is a lifesaver. <Anne, PC's can be used to keep clams, but the wattage level would still have to be high...six to seven watts per gallon. You would still be looking at a 4x65 watt fixture. Orbit does make a 280 watt combo, one 150 HQI and two 65 watt PC's, but you are looking at $430.00. I would look at HQI DIY fixtures. Either way, if you want to keep a maxima, there is no cheap way out in the lighting department. James (Salty Dog)>

Feeling Clammy (Lighting For Tridacnids) I am in search of a little help, and even with various research materials... books, word-a-mouth, and your website, I still feel clueless. <That's perfectly all right...I feel that way on a regular basis! Scott F. here today!> I have a 13 month old "established" reef in a 50 gallon. Quite a few fish, quite a few corals... all has been going well. But I recently stumbled upon a Maxima clam that I thought was gorgeous. Being a "smart" reefer, I wanted to research before an impulse buy. I currently have a Coralife lunar Aqualight double linear PC fixture, altogether 260 watts. Would this be sufficient for a Maxima clam, or any other clam for that matter?. I think they are neat to watch pulse, but I definitely wouldn't think it would be neat to watch one die due to my insufficient lighting. Thanks for all the help <Well, I think it's great that you've done your homework! Lighting can be a subjective issue among reefer, but there are some basic concepts regarding lighting and clams. In my humble opinion, intensity is extremely important with these animals for long-term success. Sure, they can be kept under PC lighting, and have been kept successfully this way by many hobbyists. However, careful attention must be paid to the proximity of the animal to the light source. In other words, if you are using light intensities that are lower, you'd need to place the animal higher up on your "reef" structure to get maximum intensity. Another thought is that you would be well advised to compensate for lower lighting by increasing nutrition, in the case of those species which feed. In the end, I think the best long-term strategy would be to employ metal halide lighting, as it provides the most "bang for the buck", IMO. Hope this helps! Regards, Scott F.>

Collegiate Crewmember Wants a T. maxima - Lighting? + Anthony's Response Hey Anthony, and\or anyone else willing to chime in: I'm going to have to downsize to a smaller aquarium when I go to a dorm, and I'm looking at a "nano" type aquarium with an enclosed hood, retrofitted with PCs and T5's. I know someone who mod.s them, and gets 9200Lux @ 1ft depth (about where the clam would be) using PC and T5 lighting. I have a 7" teardrop (gold\purple\maroon) maxima, and I'm wondering if this will be enough. I'm very wary about not keeping it under halides - think that this would cut it? If not I'll just go with a halide pendant, I was just hoping I could get away with a hood to help prevent beer in the aquarium! :D Thanks, Michael <Put that tank in front of the window, and add phyto and I think you'll be just fine. Adam> <Your concern for not keeping it under halides is wholly unfounded. This clam and a majority of Zooxanthellate creatures we see in the hobby can easily be kept in shallow water under good fluorescent lighting. No worries. Anthony >

Discrepancy on the Tridacna FAQ page Sat, 19 Mar 2005 On this particular archive of FAQs: http://www.wetwebmedia.com/tridaclgtgfaqs.htm there are some major differings of opinion in the lighting Q and A's. In one question, Anthony is saying to me that clams can be kept under PCs just fine, and on another Q and A Jim is saying never try maximas under anything but a 250w halide. <Interesting> I know that lighting is probably the fuzziest area of our hobby, and everyone's opinions are contributed to this site, but this is one heck of a differing opinion! Just wondered what everyone else thought about this. It just made me say "whoa!". <Thanks for this Mike... Antoine? BobF who is of the opinion/stance that all Tridacnids can do "well" under both types of lighting>

Re: Discrepancy on the Tridacna FAQ page - Jim Responds I pasted my reply below for clarification - you might want to read it again. There is NO hard and fast rule, and it's more a question of intensity rather than type for starters. I have seen very intense maximas dull down a bit under less than adequate lighting, although they grew and thrived despite this. I've also pulled maximas out from behind rockwork where they had fallen and been pretty much without light for months on end and were none the worse for wear. What I said was If you want a "can keep anything I want with no worries setup" go with a 250W double ended (HQI) fixture, or a 400 watt mogul setup." This will enable you to keep ANY clam, maxima or otherwise without worrying about whether or not your lighting is adequate, or whether or not it will retain the colors you see when it's shipped to you. Regards Jim "175 watts is not enough light for the more colorful Maximas - at least if you want it to retain it's vibrant colors. Tridacna maxima is actually a very adaptable species, but under inadequate lighting, they tend to lose their vibrancy. He should live and grow in your setup though, and I would recommend you place him in the top third of the tank. Also keep in mind that these animals are filter feeders throughout their lives, despite what you may read to the contrary. Add phyto every other day or so. I've kept and grown T. Maximas with great success under 150 watt double ended fixtures, but those are brighter than your 175 watt single ended setup. Brown Maximas, or even T. squamosa should do fine with your light. Again, the blue ones will live, but it's not ideal. If you want a "can keep anything I want with no worries setup" go with a 250W double ended (HQI) fixture, or a 400 watt mogul setup. 20k looks better too, IMO. If you upgrade, you can simply start the fixture fairly high off of the water, and lower it a bit each week until it's 10" or so above the water. Cheers Jim"

Re: Discrepancy on the Tridacna FAQ page - Anthony Responds <Thanks for this Mike... Antoine? BobF who is of the opinion/stance that all Tridacnids can do "well" under both types of lighting.> Agreed... all clams can be kept under any lighting. To be finessed as needed. Shallow placement under weaker configs, deeper placement under more intense... considerations for ones water clarity (or not), etc. Some of my nicest maximas and Croceas through the years have been kept under hardware-store bought daylight (6K) lamps with some old Phillips O3 blues for good measure :) 20 and 40 watt lamps ta'boot... shoplights. Ahhh... the 80's :)

Clams under power compact lighting - 11/17/04 Hi. <Hello, Sharon> I was wondering if a squamosa clam or any other clams can be kept under 400 watts of power compact lighting. <Well, based on your tank depth and size I wonder..... The answer is a bit complicated, but I would like to say "yes!" if some other points of interests are addressed and the clam is placed midway to high in the tank. You just might get away with it on the bottom as well. The tank has to be fully "aged" and by that I mean it must have been set up for a minimum of eight months, plenty of coralline algae growth, water chemistry within the suggested parameters, and have done your research on your particular species of clam as far as habitat and feeding requirements. It is important to note that clams do not get 100% of their nutritional needs from photosynthesis alone. They also need to pull food from the water. A live phytoplankton might go a long way to help in this endeavor and there are lots of quality live phytoplankton feeds on the market. I prefer Reed Mariculture's Phytofeast or DT's Live Phytoplankton. Also be sure to get your clams from a quality dealer. This is very important in that you get clams that are properly cared for in the interim holding, and also are responsible in their selection. I prefer captive bred over wild clams. As for a purchase place, I prefer Barry Neigut at www.clamsdirect.com. Period! The guy knows his stuff, extremely knowledgeable, consults with us here, at WetWebMedia and other sources, often, has a great selection of captive bred clams (WYSIWYG), good prices, really a great resource. I don't get paid to state this, this is just where I have most recently heard lots of good things, seen him at various reef gatherings, presents at them too! Do your own research and find your own source and let us know about it.> The tank is a 135 and is 18 inches deep. thanks a lot <Thanks Sharon for asking your question here at WetWebMedia. We really appreciate your participation. ~Paul>

QT/lighting for tridacnid good evening crew: I have my eye on a tridacnid clam that my LFS has had for over a month, so I'm guessing it's healthy (I'll ask some questions, check the response to shadow). I have a QT: 30 gal, partitioned into a 20gal side that I have equipped with a hang-on filter and mediocre skimmer, and a 10 gal side with a hang-on filter/no skimmer. I don't want to sink a fortune into lighting, but I don't want to compromise the clam, either. I have a 36" hood with 2 25w NO aquarium lights that I could use, or I was considering building a fixture and mounting some compact fluorescents (the kind meant for replacing normal incandescent bulbs, not PC's) each of about 20W. I probably don't have much choice in the color temperature, but if this option were viable, and I could choose from "cool" or "warm", which is best? the tank is about 16" deep. what would you recommend? thanks! Ken Baker

Re: QT/lighting for tridacnid thanks for the reply. after looking at lights of America's web site, I assume you mean their 65watt equivalent (13 watts actual) compact fluorescent floodlight. Ooops, sorry I wasn't more clear. I mean this one: http://lightsofamerica.com/floods I got to thinking--for QT use, could I use a "halogen" shop light--the kind w/ built-in reflector--they come in 100w, 200w, (500w). maybe they are totally wrong spectrum. Yep, totally wrong. Lots and lots of UV IIRC. I would go with halogens. thanks ken

Light and food for a clam dear crew, can I just using 3 fluorescent lamps 20 watt each and just white color in 2 feet aquarium? << Absolutely. But you won't be able to keep much in there. If this is just a freshwater tank, you are fine. If this is to be a mini reef aquarium, then you are in need of much more lighting. >> and also can I feet my clam with sera coral liquid? << I'm not sure I understand this question. I don't know what sera coral liquid is, but I'll recommend that you definitely do not have a clam under such small lighting. I would think that 200 watts of light is a minimum for most ornamental clams. They do well when fed phytoplankton and even some commercial zooplankton products. >> << Blundell >>

Clam Lighting Query Hello, Great time reading pages of FAQs, but still think I should inquire directly. To sweeten the deal I would like to tell you, that I believe you (all) to be entirely responsible for any success I may claim in the hobby. I have a successful (so far) 65 gallon reef system. The dimensions are 36"L x 18"W x 24"H. I have 175w 10K MH and 226(total)w PC. I have felt confident with the amount of lighting, until I began researching for the care of a 1" Maxima Clam I have just purchased. While I am fairly certain I can keep it in the top 1/3-1/2 of the aquarium, I am set on keeping it on the sand floor. -- Is the current set-up sufficient or will I, reluctantly, have to upgrade my lighting? If so what amount and variety would you recommend? Finally, if more is required what would you consider the most appropriate acclimation technique for a system that currently houses a number of photosynthetic inverts both soft and hard? Thank you very much, Jason Paul >>>Howdy Jason! 175 watts is not enough light for the more colorful Maximas - at least if you want it to retain it's vibrant colors. Tridacna maxima is actually a very adaptable species, but under inadequate lighting, they tend to lose their vibrancy. He should live and grow in your setup though, and I would recommend you place him in the top third of the tank. Also keep in mind that these animals are filter feeders throughout their lives, despite what you may read to the contrary. Add phyto every other day or so. I've kept and grown T. Maximas with great success under 150 watt double ended fixtures, but those are brighter than your 175 watt single ended setup. Brown Maximas, or even T. squamosa should do fine with your light. Again, the blue ones will live, but it's not ideal. If you want a "can keep anything I want with no worries setup" go with a 250W double ended (HQI) fixture, or a 400 watt mogul setup. 20k looks better too, IMO. If you upgrade, you can simply start the fixture fairly high off of the water, and lower it a bit each week until it's 10" or so above the water. Cheers Jim<<<

Clam lighting 9/28/04 Hello WWM Crew, Let me start by saying that I have read the FAQ about lighting and I came close to finding my answer. I am purchasing a 60x24x24 150 gallon aquarium which will house various Clams and SPS corals. The substrate will be 4 inches deep with a canopy of 12 inches. Lighting will be 2-250 watt MH 10k and 4-55 watt PC Blue Actinics for a total of 720 watts. Will this be enough? <Plenty! Absurd amounts of light are not required for most of these animals. There isn't an Acro out there that needs more light than will be provided by the upper 1/3 of your tank close to the lights. 99% will do very well just about anywhere in the tank with that lighting.> Or should I swap out the PC's for another HM (750 total watts) for the light intensity, PC's are at a distance.....possibly now 14k on the HM's for the blue that the PC's were going to supply......Thanks Steve <IMO, adding more halide will only waste electricity and leave you with no where to put corals that won't tolerate very high light. The PC's will be mostly for effect, so I wouldn't worry too much about the distance. Best Regards. AdamC.>

Hello, I'm looking into getting some clams. I have 2-175watts MH at 12000k and 2-96 watts (actinics), do I have enough light. 75 gal. reef. << Well this is rare for me to say, but... yes. I believe you do, and many many people under light their tanks. I think you are okay with that. For me, I would still have the clam up in the tank and not on the bottom. Also look for a clam in a store that is looking good, and has the same amount of light you have. Adam B. >>

Clam Lighting Hello <Hey Robert> Thanks for providing a great web site and valuable advice. I have a 50 gal reef tank with 4, 36" VHO lights 2 AquaSun and 2 actinics driven by a icecap 660 ballast. The lights are about 4" above the water and the water depth is about 15". Is it possible to keep a Tridacna Crocea or Maxima clam? Will it be ok or slowly die? <In all honesty Robert I'm inclined to say a Derasa would probably do well under those lights but it might not be enough for the Crocea or Maxima as they start to grow.> I am thinking about upgrading my lighting to MH but can't decide what wattage to go with 150,175 or 250. <If you wish to keep more clams and more SPS corals then I would suggest the 250 or even a 400 light.> I do have a Montipora Digitata about 8" below the surface that is thriving under this lighting. <Wonderful. Sounds like a very lovely tank.> Thanks, Robert Walz <Good luck Robert, It sounds like you are well on your way. MacL. > Tridacnid under Power Compacts - 2/24/04 Hi, crew from fish heaven. <Howdy> Can one keep Tridacna clams under PC lights? without MH. <Some clams can adjust better than others. Squamosa and Derasa do a bit better than Crocea and Maxima. Be sure to keep 'em a little higher in the tank once acclimated. (acclimation and feeding is very important)> I'm thinking of putting them 10-12" under the PC's. <Check out the Forums at www.clamsdirect.com. Proprietor Barry Neigut is knowledgeable (one of the nice guys in the biz) and is extremely helpful. Lots of info to be had. Oh, and check out our FAQs and articles on clams. ~Paulito> Thanks, Bernd from Honduras.

Clam placement under halides - 1/27/04 You guys rule! <Thanks> Got a 150W DE MH over a 38 gallon (22+" deep). Got 4-5" of sand. Would it be acceptable to place a T. maxima or T. crocea on or near the substrate (approx. 17-18" deep)? <Well, 150 is a little on the low side but I would go for it. Watch the clam and see how it looks. Maybe slowly move it towards the mid part of the tank or higher over time. Feel free to drop by ClamsDirect.com and ask the experts there in their forum or maybe even call Barry (the owner) and see what he says. Let him know I sent ya. ~Paul> Or is this too deep for my lighting. <Might be a little deep. Try it and watch the clam for signs of stress (i.e.. gaping extended mantle far beyond normal, extreme recession of mantle, not reacting to movement to name a few.) Good luck. ~Paul> Thanks! -matt

Clam Lighting Questions Dear WWM crew, I hate to make a nuisance of myself, but I have a couple more questions (several of them are probably stupid, but, hey, I won't know if I don't ask, right?) <Truly, the only stupid question is the one not asked! Especially if lack of asking kills animals.> I went back to the store, and the Crocea was gone (big surprise) but they now have a beautiful purple maxima for the same price. I was talking about getting it when a friend and fellow reef keeper jumped down my throat for dooming a clam to certain death by trying to keep it under VHO's when all clams MUST have MH. <Tell your friend to settle down and "don't believe the hype!"> He even pulled a reef-keeping handbook off the store shelf at random (hardly the most responsible method, I know) and showed me that it says they require MH. Even your own FAQ's seem to mention MH a lot. But then other articles say they can be kept under normal fluorescents! I know it has a lot to do with depth and distance between bulb and water, but aren't there some sort of guidelines? Can a med-large purple maxima be kept under VHO's? <MH is certainly recommended. As a general rule, the more light they get, the better clams do, however, as long as you exceed their minimum requirements, they will do fine. Growth may be a bit slower, but they will do fine. In your tank, under 3xVHO's, I would certainly keep a clam in the upper 8-12 inches.> In the same vein, I also looked at (and ended up purchasing) the most beautiful Frogspawn/Octobubble I have ever seen. It had been there for a month, under 3x4' VHO's, and was doing great. I also know your website says these corals need moderate light and current, and I would have thought my system about perfect, but again, my friend and his handbook both insist they require bright MH light and very brisk current. <The level of reef keeping has been raised since most current available references were published. What was considered brisk current then, would be moderate at best now. Your system sounds quite ideal for Euphyllias.> I must admit that I've not had luck with these before, but after reading your website, I was thinking it had more to do with the large numbers of soft corals (many of which I have removed to their own tank), and not inadequate light. I placed the Frogspawn at the opposite end of the tank from the overflow/return, about halfway down. It gets good indirect flow but no strong direct current. Does that seem reasonable? <Sounds very reasonable. Overly strong current will prevent the coral from opening, and you certainly have plenty of light. Euphyllias are quite sensitive to water quality in general, and the presence of soft corals in particular. Water changes and carbon will help ameliorate these effects.> One thing I would find extremely helpful is if your descriptions of each coral/clam/animal said something about light/current/placement requirements. I know that I read something about different clams having preferences between rocks and sand in the FAQ's somewhere, but now I can't find it, and the species descriptions don't say. Same for corals. <Any clam or coral can be kept on the sand as long as it can't bury itself. As a rule, Crocea, maxima and Squamosa clams are rock dwellers, but all can be kept on the sand as long as they get enough light.> Okay, I am sorry for the length, but I have two last questions: <No worries! Ask away.> In your descriptions of placing VHO tubes 3-6 inches above the water, I am assuming this is without a glass canopy in between? I still had one on my tank until recently. I grew up with them and never really thought about removing it until I was thinking seriously about lighting. <Give up the glass! Glass covers really do attenuate the light a lot, particularly if they aren't very clean.> Second, does my colt coral pose a major chemical warfare problem, or is that mostly a leather coral issue? Can I keep just a few green star polyps and/or frilly mushrooms in my reef tank without doing any harm, if I thin them regularly? <All softies will produce allelopathic chemicals. Sinularia (finger leathers) and mushrooms are among the worst. Your colt and star polyps are more dangerous in direct physical encounters. When you rule out all other causes of ill health in a coral and suspect chemical warfare, you will have to remove the aggressor or the victim. In the mean time, keep up the water changes and frequently changed small amounts of carbon.> Thanks again for all the advice and help. Jim <Glad to! Adam>

Doing the Fluoro Salsa.. or Was It a Rumba? >Good afternoon! For Bob Fenner and other marvelous WWM FAQ crew. >>Good day to yourself as well. How goes it? >Recently, my full-spectrum (daylight) fluorescent tube had been out-aged and cannot be used for more. After that, I ask my assistant to buy a daylight tube (I know this is seems to be not wise, because handling an knowledgeable task without supervising can make a wrong choice and creates one more problem) but I haven't much choice, I'm too busy for my stacking homework. >>Understood. >So, when he go home and I see what type of lighting he bought, I see it's a little bit different from the previous one. The light wasn't white-colored, but rather violet hued and seems not too strong to support autotrophic organisms in my aquarium. For example, my two Tridacna derasa clam (sorry -- it's not Tridacna maxima, I realized the species shortly after sending you the email) still exposes their broad mantles, but I'm not sure if the zooxanthellae can tolerate another type of lighting. >>I like T. derasa myself, my friend. >Do you know the type of lighting and is it good for my clams? >>I'm afraid not, my friend. What you would need is to look for the manufacturer's specifications on the bulb. I am guessing that you may have what is called a "warm white" bulb, in which case it will be too high in the red end of the spectrum. You should be better getting a "cool white" bulb, or better yet, possibly calling the shop where your assistant bought the bulb, tell them what you HAD, and ask if they have that same bulb. >And also for my intertidal urchin, Colobocentrus atratus who seems to love the atmosphere and always tries to creeps out of water. I'm afraid if they will develop air bubbles in their test cavity, and slowly dies. >>No, I doubt they would harm themselves in that way. >Should I constantly replace the urchin back to water or just leave it alone? >>As long as it cannot escape from the display completely (and get lost?), leave it alone. They know where the water is (DOWN!), and will go back when they feel the need. >Thank you very much for previous helpful emails !! Sincerely, Anargha. >>Alas, I, Marina, cannot take credit for those, but will offer that you are welcome all the same. Marina

Maxima clam lighting - 9/3/03 Greetings WWM Crew! <Hello Kev. Paul here to help> Thanks for your dedication, expertise, and this website. <Yes, indeed. Thank you Bob!> It is an invaluable resource. <Agreed and always much improving thanks to your query!> I would like to add small Maxima clam to my 10 gal reef, but fear my current lighting is insufficient. It is a 28W, 10,000K 50/50 that stands on legs such that the bottom of the light fixture is 2.5" from the water surface. The spot I would like to place the clam is about 2" below the water surface and there is no lid on the aquarium. <Hmmmmm. I think this is grossly insufficient.> Is this enough light? <Unfortunately this is unsuitable for any clam. This is quite a small tank for such an inhabitant (it can be done though), but more light is definitely needed before adding such a beautiful animal. Lower light clams are more along the lines of the Squamosa clams but again there just isn't enough light here. Give a call to Barry at www.clamsdirect.com. He is super knowledgeable and offers great advice on what you will need to keep clams o plenty! -P> Best Regards, Kevin.

Clams under PCs? 9/1/03 I think this one is for Anthony or Bob. I was reading the Reef Invertebrates book and there was a section that stated you could keep certain clams under PCs. <you can keep even the most demanding SPS corals and clams under standard fluorescent lighting as long as the bulbs are properly close to the water (no further than 3" off surface) and the invertebrates are kept shallow enough (less than 10" of water)> My tank is a 125 gallon (72x18x20), actually 112, but sold to me as a 125 :-( Anyway, I'm in the process of upgrading everything on my tank. I'm adding a sump/refugium, live rock, more lighting. I currently have 2 96W Smartlites, but am going to add two more 96W fixtures. I was planning on having 2 10,000K and 2 Actinics. Would these be enough to keep clams? <indeed... no worries. Do keep your most demanding creatures like clams with the top 16" of the surface under PC.s> Thanks, and I love the book. I just purchased the BOCP. <thanks kindly... will have it posted promptly tomorrow! Anthony>

Clams Lighting - 8/19/03 Hello there, <Hello from California> WWM makes sourcing for information on Marine creatures so much easier for me. Great site! <Thank you kindly> I've read through the FAQs on Clams, but I haven't been able to find out how much lighting I would need if using T5s. <not familiar with TSs. Enlighten me, please> I was wondering roughly how much light I would need to keep lets say, T. Maxima and T. Derasa in the upper 1/3 of a 3 x 2 x 2 tank? I am currently using 2 x 39W Aquablues from ATI which is 60% actinic and 40% white...<Not nearly enough, but again I am not familiar with your lighting scheme here> I know this is grossly insufficient if I base it on the watts per gallon rule, <Not all about watts per gallon> so I would like to supplement the lighting. <Are you able to get your hands on halides or equivalent? This seems to be the light of choice for Maximas and Derasa clam keeping.> Question is how much more do I have to supplement, and which type of lighting would be more relevant for clams? 10000k or Actinic? <Brighter of the two but I would try to keep both. They both service different parts of photosynthesis to a degree. Read about lighting invertebrates, not necessarily only about clams. See here: http://www.wetwebmedia.com/marlgtganthony.htm http://www.wetwebmedia.com/marcanopies.htm http://www.wetwebmedia.com/marine/setup/lighting/faqs1.htm (these are good starts). Also, I have a friend in the clam business... Barry Neigut. Check out his site at www.clamsdirect.com He is a great resource for information (kinda got his start here). Sign up for his forums, send him email, call him even. He is a super guy and very helpful. Tell him "WetWebMedia sent ya!" -Paul out!!> Thanx! Zhuomin (Singapore)

Maxima Clam light 4/22/03 I've read through the FAQ's and the link to the chapter in your new book, but I am still unsure as to whether or not I can successfully keep a T. maxima. <OK> I have a 75 gallon tank and run two separate PC fixtures and a twin tube fluorescent fixture. One PC fixture has two 50/50, 65 watt bulbs (130 total) and the other has two 50/50, 55 watt (110 total) bulbs. These two fixtures are at the front of the tank. The dual tube fluorescent fixture sits at the back of the tank and has a 10,000k and an actinic bulb that amount to 70 total watts. Do you think I could keep a maxima if I place it on a rock about 6 inches under the lights at the front of the tank (under the pc's). <yes... easily> I believe I have the perfect spot for one, that is, if the lighting is adequate... <agreed> Oh one more thing... will it be bothered if I place it next to Xenias? <not likely at all... Xenia is quite passive> Thanks <kindly, Anthony>

Clam lighting recommendations Thanks now for my lighting what would you recommend for my 24" cube, I would like to keep a clam or two. I am looking at MH & PC lighting. Thank Dave <Hi Dave, For clams and high light demanding inhabitants, a 175 watt MH (or 250 watts) perhaps with two VHO or PC actinic bulbs to supplement the blue spectrum would be ideal. I would favor the 250 watt for the depth and they are available in a "radium" which may do away with the need for actinic lighting. The color rendition is a personal choice, you may want to look at clams under different types of lighting to "see" the difference. The blue light will definitely help "fire" the colors of clams and corals. For PC's try to find "true" actinic blue bulbs. I prefer VHO myself, with Ice Cap ballasts very flexible. (Can drive PC/NO/HO/VHO). Have Fun! Craig>

Clam lighting for a 75 gallon Hello there, I have a 75 gallon tank with two of the 48 inch Aqualights, which total 520 watts of light. Split it would be 4 10,000k bulbs and 4 actinics, which are 65 watts each. Anyway, would this be enough light for 1 or 2 clams if kept in about the middle of the tank or closer to the top? Jim >>Wow, Jim! First, have you gone through this section on our site?--> http://www.wetwebmedia.com/tridacnidart.htm Here is some more information specific to lighting questions--> http://www.wetwebmedia.com/marlgtganthony.htm >>Part of the issue is species of clam, for instance Tridacna derasa and Hippopus can do well with lower lighting. I'll assume that you would like to know which species you can keep with the lighting you have available for them, and I see no reason why you couldn't keep either of these species. If you wanted to get something like T. crocea, then I would be sure to place it higher up. >>>>Ok guys, I'd like to bump this to someone who REALLY knows their stuff on the clams. I've spent about an hour reading through old FAQ's and as many articles that appear to be related, but I feel I can't give a very complete answer regarding which species will do well with his lighting, or which might be better, as I've not had experience with every species. Also, because of this lack of experience, I can't tell him which species *can* be placed up on rockwork, and which others will do better on the tank bottom. Nor can I advise him on specific bulbs, and I don't want bad information to slip by or to have left something important out. Thanks!<<<<

Crocea Clam lighting 3/15/03 I would like to buy a Crocea Clam and would like to know how close to the lights it would need to be. Its a 55 Gallon tank 20 inches deep with 4 36inch VHO's 2 Super Actinic URI 1 Actinic White URI 1 Aquasun URI <within the top 12" of the water surface will be fine, my friend. Have you read the sample chapter on Tridacnids from our new book, by the way? Click on the chapter link on this page: http://wetwebfotos.com/store/nma-ri.html best regards, Anthony>

Clam Lighting How many hours per day of high intensity lighting does a 2-3 inch maxima clam need if it is placed in a 20 inch deep tank with 2-175W metal halide bulbs suspended 12 inches above the surface of the water? <<Hi Jacqueline, Craig answering while the WWM crew is attending MACNA. Clams are light hungry and require the highest intensity lighting. Even with 175 watt MH's I would still place this clam close to the top of the tank. The very minimum would be six hours a day with the best of light but I would about double that to ten to twelve hours for your clam to grow and thrive. I personally use 12 hours. Small clams do well placed in a removable container so they can be target fed with phytoplankton. Feeding is actually more important for small clams than light at this stage, although they need the best of both to thrive. Cheers, Craig>>

Lighting for Maxima Clam How many hours per day of high intensity lighting does a 2-3 inch maxima clam need if it is placed in a 20 inch deep tank with 2-175W metal halide bulbs suspended 12 inches above the surface of the water ? <9-10 hours would be appropriate. Maintain good water clarity (prevent yellowing) by small weekly changes of carbon rather than once monthly. Daily skimming and regular water changes too of course. Best regards, Anthony>

Lighting for clams Dear Bob, <David D. taking questions this evening.> I have read many marine fish books, your book, "The Conscientious Marine Aquarist" is by far the best, am eagerly waiting for your crew's new book on reef inverts. <It is also the book that got me started in the hobby!> I am confused on the issue of lighting. I have a 55gal reef with 2 clams which I placed on the top part of the tank. Based on watts per gal, I am way below the requirement. <Watts per gallon is a poor rule. Think about it...If two tanks were 100 gallons and one tank was 20" deep and another 30" deep, would they need the same amount of lighting to keep clams or corals?> My tanks is 36" wide and I use 4 fluorescents, 2 marine white and 2 actinics by Arcadia (a UK company). The lamps are only 18 watts each with 9,500Kelvin. Over the weekend, I changed one marine white to one Coralife white with 10,000 K, also 18 watts. The shop tells me that my lighting is sufficient, I am not sure although the tank is very bright. I read John Tullock's book, "Simplified Reef Keeping", which said that 4 fluores. with 2 white and 2 actinics is enough for a 55 gal reef tank. I am not sure as your book did not go into very detail on VHOs. please advise. <If I understand you correctly, you have 4x18 watts=72 watts. At this low level color temperature is almost irrelevant. It just isn't enough light to keep a clam alive...Not even close! Maxima clams need lots of light. If you want a watts per gallon, assuming your tank is 18" deep or less, I think you need 5-7 watts per gallon with any kind of fluorescent light fixture. The clam would still need to be in the top portion of the tank. At first the clam will look really large and happy in your tank. Actually, he is swelling to catch as much of the light as possible. Within a few weeks maybe sooner, those beautiful colors will start to fade or he may eventually close up. Either of these events will be the beginning of the end. I would take these clams back and find a new fish store...> The other question is on the brand. I noticed that the Coralife lamps is clearer and whitish/more transparent while Arcadia's is more yellowish and brighter, can you tell me which is a better lamp as Coralife's price double that of Arcadia <I've never heard of Arcadia. But for standard fluorescents, Coralife are good. For VHO? URI.> Thank you. <Your welcome!> Regards, Daniel Kong <Daniel Knop has an excellent book about clams. Also search wetwebmedia.com for more information. Good luck!>

Lighting for clams Dear David, Thanks for the instant reply, what a pleasant surprise! <You're welcome my friend in fish!> If I do not want to use metal halides and use VHO instead, what sort of wattages is recommended, <With VHO I would shoot for 300 (maybe slightly) more watts> as I was told that the MH creates a lot of algae. <Nutrients, phosphate and silicate create the algae. Light just helps it proliferate.> My tank is 19" deep, can my corals survive? <With the 4x18 watts that you currently have? No.> They are star polyps, bubble coral, a leather and a sea mat, xenia and a colt coral. <None of them long-term...especially not the bubble.> I have them for 3 months already and they seemed to be happy, they open fully when the lights are out for 14 hours (11 hours with four lamps and 2 hours with 2 lamps, 2start 1 hour earlier and the other 2 ends 1 hour later). The clams I have is already 6 weeks in my tank and so far the colors are still intact. <Remember what I said about things "looking happy?" They're stretching out trying to catch all the light they can. If 75% of your food (photosynthesis) came from the sun, what would happen if you only got 72 watts when you normally lived outside in the ocean getting full sun all day...every day? You would eventually starve. So will they...I'm afraid. Watch the critters carefully.> Thanks again for your advice. <You're more than welcome. Don't just take my advice on this. Research carefully.> Regards, Daniel <Lighting is a complicated issue but IMO this situation is pretty clear cut. David>

Clams light problem Hi there, Your fan from Turkey :-) need your help again. <cheers, my friend from afar> I have 50 gallon setup which I have Hamilton Power Compact 3*55w 10K, 1* 55w true actinic, also NO 2* PowerGlo 30W and a 1* Marine Glo 30W/ Lights are 1" from the surface of the water, it doesn't have plexi or protection from the water. <all excellent and installed properly> I have got a clam 2 weeks ago, I believe it is Tridacna crocea Metallic blue. The clam was put in 2 inches below the water. All seems fine, but I have noticed that the clam mantles started to have flaky burn type markings on them. All over the mantles. It looks like skin burns. Since then I moved the clam down to the sand and I hope it will get better.10" below the water line <hmmm... its OK to put this clam lower, but not for too long (2-4 weeks only). The symptoms do not sound like a burn from bright lights. Excess light would cause bleaching (paling in color) from the zooxanthellae being expelled. The clam would also let go of its foot in such a circumstance and tumble to a lower/darker place. It sounds instead to me like a problem with a predator like a damselfish or dwarf angel picking occasionally at the mantle> I also have a bubble tip anemone in the same aquarium last six month just 4" below the waterline, it always hide, it is glowing white color. It feeds well and seemed happy with 3 ocellaris clown. But it does not grow and the color do worry me. <yes... the white color is a problem for lack of symbiotic algae. If this occurred after you bought the anemone, we may have a light or water quality problem. If the anemone was white when you bough it however, it is unfortunately too common. Feed well (daily ) regardless, while we wait for this specimen to regain color> I douse regularly carbon, so my water is always clear. <very good> >Do you think it is the UV from the lamps ? <doubtful... little from these fluorescent bulbs> What do you suggest for me to do? <you can experiment with a thin glass or acrylic lens between the lights and water if you like... but is must be cleaned weekly at least> Murat Ozturan :-) :-) :-) <best regards, Anthony>

Clam & Lighting Hi again and thanks for all the help. I don't think any of the LFS would even come close to the help that you have given me in the last few months. I put my 5" crocea in the QT last night and today instead of only opening a half inch at the most in the main display he/she/it is open half way. YEEHAA!!! I am making sure to check my pH, temperature, S.G. and alkalinity are all close to being the same when I do a 5 gallon water change from the main tank to the sump. I don't have the Fluval 404 on the QT yet and am waiting another few days to make sure it is more seeded before putting it on the QT indefinitely. I have the clam and the rock on the bottom of the 20 gallon QT under the 110 watts total of PC lighting. IYO, do you think I should raise the clam to within a few inches of the PC? <No, I would leave as is.> I feel it would be a good idea and should probably shield the PC from the clam blowing water on the lights as well. Will this much light be enough for it considering it was under 400 watt MH's and also receiving light from some 160 watt VHO's on the bottom in my 180 gallon acrylic? <It is heard for me to guess an approximate amount of needed light. You need to determine if 8 watts per gallon under 24" is similar to 5 watts per gallon in 12". The color and behavior of your clam is going to tell you. I would probably leave as is unless I saw a problem as I am very reluctant to move any photosynthetic creature once placed.> More help would be totally appreciated! Thanks, Jeff <You are welcome. -Steven Pro>

Light on Clam would 200 watts of CSL Smartlight be enough light for a small clam (maxima) on a 55 Gal tank??? Thanks Jeremy <yes...very fine, but do be sure to keep clam within top 1/3 of tank for best success. Clams really do enjoy bright light, and fluorescents do not penetrate deeply in water. Kindly, Anthony>

Squamosa clams dancing the Irish jig <Anthony Calfo preparing myself for the upcoming trip to Germany...eating sausage casseroles, sausage omelets, sausage pie and sausage milkshakes...with a sauerkraut garnish. All washed down with warm dark beer. Nobody light a match!> Hi again! <Salute> I have 2 squamosa clams that just will not keep still. <when you've got a good song in your head, it is hard to resist finding a groove... cut them some slack, my friend> I place them on a flat surface and the next morning they are on there side or on the sea floor, I have more than enough lighting ( I am the guy who is making lava in his tank) <Ahhh, yes... I remember... 400 watt halides over 2" of water... making steam. How you 'doing?> my T. Maximas are all doing fine and staying put. <like deer in 400 watt headlights...heehee. I'm just joking of course (thanks for being a great sport...and target <wink>). High intensity lighting is very appropriate for T. crocea and T. maxima clams, in particular> I don't understand there fully expanded taking in all the rays I give them but they keep moving. Someone said to me you better move them from that spot cause they aren't happy. <nope... I disagree. As much as I enjoy teasing folks with big watt MH on aquaria less than 30"... too much light is not your problem in this case. I had the pleasure of having two XL squamosa clams (12-16") spawn in my greenhouse. They were in full sun with barely two inches of water above them and supplemented with a 400 watt halide (ahem)> Well I have moved them to other areas of my tank and I still get the same results. <Aiieee! A good way to stress/kill symbiotic animals. Never move photosynthetic reef inverts even twice in one week through different light intensities...especially when new (having been imported and run through 2-5 light intensities through the 1-2 week chain of custody on import). Very stressful for the animal to compensate for especially if their fatty storage is low.> Currently now I have one in the sand and the other on a ledge where I have a blue Staghorn coral. so, tell me what can I do just leave them be??? <best if placed on a piece of rock to protect byssal port from predation by segmented worms, crabs and especially (although not foolproof) Pyramidellid snails. The chap on the sand can simply have a flat rock placed under it and buried in the sand. I'd actually place both clams on a flat rock in the sand. This will leave room for maximum growth for this species the third largest Tridacna species. Reaching 18" in well under ten years. Plan for this kind of growth. They are moving because they simply want to be lodged in place in case of a storm (that will never come in your tank)... kind of. Once they are where you would like them to reside, place a temporary campfire of rock rubble around them to hold them in place. After a few weeks of being unable to move or tumble, they will set byssal tissue down to the rock under them... after which you can remove the rubble campfire and better enjoy them aesthetically. Kindly, Anthony Calfo> Tired of moving......... Walter

Lighting for T. maxima Hi Bob <Hello. You got Steven this morning, doing my little part.> Hope all is well for you these days. I have read over your site on lighting for clams and I am still a little confused on what lighting I can use to successfully keep T. maxima. My tank is a 120gal 4x2x2FT. It is a very successful Berlin system with 200lbs of Fiji live rock and about 150lbs of Fiji live sand. It has all of the usual SPS, LPS, and soft corals and inverts. My sand bed is 4inches deep. My lighting is a CSL 48INCH halide hood. The halides are 2 250watt 10K's with 2 65watt pc actinics. Will I be able to keep these animals thriving and well with this amount of lighting? <That seems like plenty of light for what is really just 20" deep at over 5 watts per gallon.> Thanks in advance. Take care. <You are welcome. You too, Steven Pro.>

Lighting requirements, selections Hi Bob, I would like to add a clam or two as well as SPS corals to my 50 gallon reef. I don't know if my lighting is good enough. I have two AGA fixtures 110 watts each of PC's. One of the fixtures is 110 watts of actinic lighting, the other is 110 watts of 9700K daylight for a total of 220 watts. Is this strong enough lighting ? Can the clams be placed on the bottom of the tank in the sand bed ? <Should be okay... would be better to have more "white light" wattage... but no worries. The Tridacnids will just grow more slowly, not be as open, colorful. Bob Fenner> Thanks for your help, Mario

Clams Hi Bob! How's it going? I just had a few quick questions for you. I am considering buying a cultured crocea or derasa clam. I have a 55 gal aquarium, 18" deep, w/2 48" VHO's (03 and 50/50) Is this enough light to sustain a clam? <Mmm, not really... need, could use about twice this luminosity> Could I put it on the bottom, or would it be better to find a flat surface about halfway up? <Near the very surface... Bob Fenner> Thanks in advance. Erin

More PC's for deep tank, Tridacnids? Hi Bob Boy I love this site!! I get most of my questions answered without bothering you, it's great. Thank you very much! I just finished checking out the queries on reef lighting. Don't take offence, but I'm still a little confused. <No worries, help me to be more clear, complete...> My tank is a 120gal. and with all of my live sand it is 20inches deep. I want to get some maximas, but don't want to switch to halides. I have CSL 4 96watt PC If I get another hood with 4 more 96watt PC's, can I keep the clams on the bottom, and still keep them happy and healthy? <Yes> I don't want to put them high in the tank like some folks do, just want to keep them in the sand bottom. I hope the 8 96watt PC's will work, halides are too hot to leave them burning while I am not at home, Also the electric bill will be sky high!

Another Lighting Question Hi Bob Sorry to bother you again with another lighting question. My 120gal reef tank, has one set of the 4 96watt PC's on it. If I added another set of the same 4 PC's on it will I be able to keep SPS corals and maxima, and crocea clams healthy and happy? <Should be, yes> The watts per gallon would be 6.4 per gallon. The reason I am asking is that the PC's are much cheaper to run as far as the electricity bill goes. They don't get as hot either , also the bulbs last MUCH longer. The PC's are also much cheaper to purchase. I know that the wattage is there, but I didn't want to purchase anything yet till I found out all of the info I can on this. Your honest opinion will be greatly appreciated. thanks <Yes... and do seek other reliable sources. Bob Fenner>

Maxima Clams, Lighting Hi Bob Just a quick question, I have a 120reef tank , 24 inches deep. I am getting conflicting theories as to keeping maxima clams with the lighting I have. Jerold from flying fish express tells me that I will be able to keep them on the substrate, and that they will be just fine. The fellows at champion lighting tell me that I should keep them about half way up the tank. can you clear this up for me? I really like only the maximas, and the Croceas, but I don't want to purchase them if I can't keep them healthy. thanks and take care.

Clams Hi Bob, I'm considering adding a clam to my reef tank. I'm not sure if I have enough lighting to maintain them properly. I've got a total of 300 watts of VHO lighting, over a 92 gal corner tank (24" deep). Would this suffice if I kept the clam approx. 12" below the bulbs? <Should, though more intensity, CF, MH would be better.> I also have 20 hermit crabs and an emerald crab. Do these pose any threat to the clam? <Some species of hermits can be harmful to Tridacnids, more if hungry... Mithrax rarely> Thanks again and hope all is well, Tony <Do buy, read over the various "Clam Books" before investing my friend. Bob Fenner>

Clams Hi, I am in the market to purchase a giant clam, either a maxima, or similar type. My alkalinity is about 10 DKH and Calcium is about 400 ppm. Lighting consists of 2 ,55 watt power compact fluorescents . One actinic and one 6700 day light. The tank is 16 inches deep ,it's a 20 gal High. Could I keep the type of clam I have mentioned above or other giant clam? If I kept one of the maximas or Croceas would I have to place them very close to the light , near the surface? If I kept a Derasa how far away could the clam be placed away from the light source? Thank You, Adam Matt >> Thanks for asking.... and for the depth of system, type of lighting I would place any of these Tridacnids on/near the bottom... the likelihood of environmental variability and toppling in shallower reaches/placed up on rock, is not worth the risk... Place whichever one you like near the middle on the bottom, IMO (of course). Bob Fenner

Clams Bob- Are two 96w PC strong enough lighting for a clam? The tank is 18" deep so I am guessing I would have to put it somewhere in the middle of the rock. Thank you, Rob >> A Tridacnid? Should be enough at even the bottom for sustaining any of the given species available... DO try to secure a cultured individual (as opposed to wild-extracted)... Bob Fenner

Lights I have a 30L reef tank and currently run two 36in VHO lights, 1 blue and 1 white. Is this enough light for hard/soft corals and clams? Also how long should I run the lights, and between what times is best? Thanks, Rob. >> For many hard corals... most every soft coral offered in the trade... and moderately for giant clams... With these sorts of animals twelve hours for the white, fourteen for the blue... an hour before/after the white. Bob Fenner, who says/keys, "you're welcome".

Clams I have a few questions first off I was wondering if there are any butterfly fish that a reef safe? Second I wanted to know what kind of lighting is needed to keep clams alive? >> IMO yes... some of this family (Chaetodontidae) are largely zooplanktivorous (though, of course there are gradations to almost absolute coral polyp feeders). Some examples: The Longnose Butterflyfishes of the genus Forcipiger... Chelmons, Chelmonops species, the Bannerfish genus members: Heniochus, the Raccoon Butterflyfishes, Chaetodon lunula and C. fasciatus... There are others, and the family, it's uses detailed in articles stored at www.wetwebmedia.com Clams? As in giant clams (family Tridacnidae) require bright/intense, full-spectrum lighting to optimize their growth and color... most folks use Very High Output Fluorescents on the low end to Compact Fluorescents and Metal Halides on the high... depending on tank depth, desired effects.