 |
|
| Home | Marine Aquariums |
Freshwater Aquariums |
Planted Aquariums |
Brackish Systems |
Ponds,
lakes & fountains |
Turtles & Amphibians |
Aquatic Business |
Aquatic Science |
Ask the WWM Crew a Question |
| Please visit our Sponsors | ||||
Combo lighting MH and T5
4/1/12 Upgrade... Tank size... sump and lights
too? 11/29/11 MH Height (much to do with stocking,
wattage, bulb K-value'¦and the reflector used!) --
10/29/10 Lighting Question'¦VHO or MH? Blue
or White? -- 04/18/10
Limited MH Lighting Options Available...What's Best For 43' Deep Reef? -- 11/13/07 Hey guys, <<Hey Marc>> Have been through your website, fabulous amount of information. <<Indeed...is quite the collective effort>> Had a question for you, more or less your opinion on what I should be doing actually. <<Always happy to present my opinion>> I have a 380 gallon reef/fish tank which is 43" deep. <<Mmm...I hope you are seven-feet tall with a 45' reach...>> It currently runs 4 x metal halides, 400 watts and 25,000K. <<Quite 'blue'...with this depth tank/lighting I'm thinking 'deep water' reef environment...>> I know that it should have a blue tint to it, but it really doesn't seem too. <<...?>> The lights themselves do, but the actual water seems quite white. <<Unless there is something 'wrong' about these bulbs, you are likely just 'used' to them. Replacing one with a lower Kelvin temperature; say 10000K, would probably reveal a stark contrast>> There isn't much space in the installation for additional lighting. <<I see>> It's relatively difficult getting MH bulbs here, it has to be mostly imported at great expense. <<Uh- oh...where is 'here' I wonder?>> The only readily available & cheap bulbs are 6,500K. <<Hmmm, Iwasaki maybe? This Kelvin temperature is really quite ideal for 'reef' applications. It contains quite enough 'blue' light for the photosynthetic organisms and provides the most PAR/best penetration over most other 'aquarium' bulbs. But...most hobbyists do find it to be too 'yellow' for their tastes>> Do you think if I switched to 4 x 6,500K this would make a large impact on the aquarium or the conditions for the reef? <<Indeed...as just mentioned>> Is their a way to get a bit of blue glow into the water? <<Oh yes!>> Perhaps some small lamps, but would they penetrate the 43"? <<Some 48' 54W HO T5 Actinic lamps with good reflectors should serve this purpose. They will provide little 'useful' light at this depth (leave that to the metal halides), but should give the 'appearance' you are after. Just 'how many' will be up to your sense of aesthetics>> In a nutshell, what lamps do you suggest I run for best conditions for the reef taking into account my fixtures and/or same question, but taking into account I'd like a bit of blue if possible. Thanks! <<As outlined...but do feel free to write back if I've not been succinct. Eric Russell>> Regards, Marc Steeb Lighting Choices Over Large Aquarium...some corals 3/13/07 Hello, <Hi.> I have just set up a big tank and need to add some lights. I need your advice on what to go for. The tank is 3000litres, 3.2 metres long by 1.3 metres wide and water depth is 0.8 metres. <Mmmm so roughly 667 U.S. gallons....sorry we aren't on that system yet.> I have a lot of live rock and added some more Fiji rock a month ago. I do not have any hard corals but I might add some soft corals later on but I'm more into my fish. <Okay.> So I'm not sure how strong to make the lights. Here in South Africa, I can choose from the following Aquamedic lights: <Hello.> 1.2 metre Sunbreams which are 1 x 54w actinic t5 plus 1 x 54 watt white. How many would I need? Aquasunlight unit which is 2 x 250 watt metal halide and 2 x 54 watt t5s. Aquasunlight unit which is 2 x 150 watt metal halide and 2 x 54 watt t5s. <I would go with he 250's simply for sheer size of the aquarium. If you are planning to keep the corals centralized in the middle of the tank, these systems could be fine but if you want to keep the all over a larger span of the tank....one consisting of at least 3 MH bulbs would probably be better. Just FYI.> Many Thanks, <Of course.> James. <Adam J.> Too much MH lighting? 11/26/07
Hello WWM crew, <Hey George, JustinN here with you on this fine
evening> I have a concern about lighting. In your opinion, is 1200
watts for a (@ 200 gal.) 33" deep x 72" long x 24" wide
reef set-up too much? <Mmm, all depends how its distributed across
the tank.. May be a bit excessive for your plans.> I am not
attempting any SPS species. Mostly soft corals, some Trachyphylliidae,
and Caulastrea. I do get more algae on acrylic then I like, but a trade
off I guess. Nitrates =0 Phosphates=.2 Ca++= 475-485 Alk= 4.5 pH= 8.4
salinity= 1.025 <Identify the source of your phosphates, and I'm
sure you'll see a decrease in your algae buildup, however, diatoms
on the glass are pretty much an inevitability.> I have thought about
cutting back to about 4 watts per gallon. My concern is that I have two
T. Crocea's at the substrate. Will that be sufficient for them?
<Should be> I have been employing other controls for algae as
well. I tested my salt mix and phosphates run zero. I do twice monthly
water changes, utilizing RO water, of course. And, I try to not
overfeed, but probably do a little, like everyone else. <Try
increasing this water change regimen to weekly, and you will likely see
a subsequent decrease in both phosphates and diatom growth.> I read
on your site that you recommend phasing the light source for a reef,
and that makes sense due to the limit of 'peak' sunlight in
natural reefs. Is there a way to attenuate the MH lights so that they
are not blasting all the time? Like a dimmer, I guess. <Bingo.>
Thanks for all your fantastic insight. Regards, George <Cutting back
on your light will likely have no deleterious effects, especially if
done gradually, and may have a positive effect on your pocket book.
Hope this helps you! -JustinN> Supplemental HQI Lighting On A 900 Gallon Tank 8/6/06 Salutations! <Hello Tim> I'm currently in the process of setting up a rather large aquarium, a 10' x 4' x 3' monster (3 feet deep). The tank is acrylic, and has 3 large 30" square cutouts on the top. My setup is as follows: 1) I live in Arizona in a house with a flat roof. 2) I installed 3 24" Solar tubes in the ceiling directly over the tank. The tubes extend down to about 18-24" off the top of the tank, and don't precisely line up with the cutouts. The two on the ends are slightly to the outer edge of the tank, and all three are more towards the back of the tank. (Joist placement issues) 3) The tank is in a dedicated room, (front of the tank is picture-frame style into the living room) so aesthetics of the fixtures is unimportant. 4) I plan to dedicate this tank primarily to shallow water SPS and clams. I suspect that the three solar tubes, while providing a huge amount of light and hopefully offsetting my electric bill, will not be enough light for this tank. I also think that for aesthetic reasons, I will need some blue or actinic lights to offset the natural sunlight coloring. Along those lines, my current thinking is to add three 20,000K 400W HQI MH fixtures to the tank. However, because of where the tubes are, these would be centered more towards the front 1.5 feet of the tank. I'm concerned that alot of my light will go directly onto the sandbed and the living room out the front face. I was thinking perhaps I could angle the fixtures towards the rear of the tank, but I'm not sure if this will cause a high loss of light through reflection off the water surface. The other option would be to put 2 halides over the braces between the solar tubes, but I am concerned about the effect of the high intensity light being directed directly at an acrylic panel. I suspect I will end up mounting a fan on the wall blowing crosswise across the entire tank to keep the heat down. Also, the room is air-conditioned. So: What kind of supplemental lighting would you recommend for this setup? How would you position the lamps? Is a 400W HQI too much power? Maybe some other combination? I can always also run them for only a few hours each day to simulate a mid-day-sun. Any other thoughts on lighting this monster? <Tim, a few questions before I can proceed. First, is the tank currently set up and running? If so, are any SPS corals or clams in the system at present, and, how are they looking with just the solar tubes? James (Salty Dog)> Tim Re: HQI Supplemental Lighting on 900 Gallon Tank...Mmm, How Many Solar Tubes Per Gallon? 8/7/06 > <Tim, a few questions before I can proceed. First, is the tank currently set up and running? If so, are any SPS corals or clams in the system at present, and, how are they looking with just the solar tubes? James (Salty Dog)> No. The system isn't up and running yet. I'm just about to add live rock and begin the cycling process. As far as the lights.. I think my primary concern is not to over-power the corals. I realize I may be in a bit of uncharted territory here. I will say, that the tubes light up the whole living room through the tank, and the light rays seem to be fairly direct, as I get the ripple effect like a MH light would. But hey. I'll have the most accurate moonlight system of anyone. <Tim, to be honest with you, I'd see how things go with just the tubes. You may have enough light here along with eliminating heat problems from 400 watt lamps. See if your investment works before spending more money. Also, in future replies, please include/reply to previous correspondence. James (Salty Dog)> Tim Another one of those Lighting Questions 11/16/05 Hi, I'll make this short, I have a 300 gallon, standard size 8' long x 30" high. I have gotten rid of all of the sharks and eels from it and am taking my existing reef tank and moving everything to the 300 and downsizing to one tank. From there I will the begin the long and expensive process of populating it. So, I already have 2 175 12,000k Sunburst bulbs on the 100 reef. I want to utilize the 175's so that I can save money, so what I am considering is 2 250 watt 14,000 halides on either end and the 12,000 175's on the inside, along with 4 65 watt Actinic PC's. <For looks, I'd put the brighter, higher watt MHs in the middle.... the lower on the outsides> Now, keep in mind that I live in the Los Angeles area and electricity is really expensive. <Am just south of you... and understand> If I can have SPSs at the top of the tank I would be happy and all other mushrooms and LPSs lower in the tank. What do you think?? Thanks <Can be done. Bob Fenner> Metal Halide Lighting with Acrylic Tank 12/20/2005 Hi
Girl(s) and guys, <Hello Jem> I have spent more hours than I care
to remember reading information on your site. It really is
something to be very proud of on your part and has taught me so many
things, however I am still slightly confused regarding MH lighting. I
have a new acrylic aquarium 120" l x 30" h x 24" w (305
cm l x 76 cm h x 61 cm w)<WOW!> and am planning on putting two
Arcadia 3 series pendants one 160 cm and one 110 cm pendant over the
tank for light. I am planning on having 5 x 250w MH and 2 x
58w and 2 x 30w linear fluorescent actinic tubes. The set up is for a
full coral reef tank with hard and soft corals and Tridacna clams.
Could you let me know if you think this is enough or too much light for
this aquarium and what height I need to keep the bulbs above the tank -
is 8 - 12" about right, <Yes> as I have read so many
differing heights for placement of MH lights in various
places. As it is an acrylic tank it has large covered areas
of acrylic across the top of the tank and two large uncovered
areas. Presumably, and from what I have read, the MH bulbs
should not affect the acrylic on the tank - is this so? <Yes, heat
will affect the acrylic if the bulbs are too close without fan
cooling.> if it does affect the acrylic what other options do I
have? or do I have to try to place the MH bulbs in the areas where
there is no acrylic covering? <I would have lids made for the two
large openings. The acrylic does act as an excellent UV
filter.> Is it possible to put MH bulbs inside a canopy of an
aquarium? I assume they would be too close to the top of the
acrylic tank and water surface? hence the use of pendants by most
people. <It's done all the time but on a tank 10' long it
would cost a pretty penny to have one made out of furniture grade wood
and probably a gazillion cooling fans.> Also what is the best light
range to have 6500K - 10000K or a mixture of 6500K - 10000K and 20000K?
<I like the 10K to 20K range.> Can you have too much lighting for
marine fish? <Yes, but you shouldn't> i.e. is the
amount of light I am planning going to affect the type of fish I can
have in the aquarium and if so where can I get information on this
matter. <Search our WWM for info on fish before you buy so you know
their requirements. Getting back to the lighting, with your
30" deep tank, the 250watt bulbs will be borderline, especially
with the pendant where they will need to be about 10" above the
acrylic. If this were my dream I'd go with five 400 watt
MH systems and place one light one foot from each end and the remaining
three at two foot centers for an even balance. I'd also
eliminate the fluorescent tubes altogether. I'd also consider air
conditioning this room also. James (Salty Dog)> Thanks in
advance for your help on my questions. <You're welcome and Happy
Holidays to you.> Regards Jem Lighting/Metal Halide Upgrade - 03/09/2006 I have a 300 gallon reef tank. I am using Three 250Watt Metal Halides and four 110 watt Super Actinic VHO's. My SPS are at the top of the tank about 4 inches below the water and have never done well and always turn brown. I have all types of corals and fish. My tank is 24" deep by 96" long by 32" wide. The lights are 14" from the bottom of the bulbs to the surface of the water. I am considering replacing the 250 Watt with 400 Watt Metal Halides in hopes to create a healthier environment for my corals as well as being able to keep SPS from turning brown. Would this be a beneficial improvement/gain for the corals or only a gain for my electric company. <In a 24" deep tank that large, a definite improvement.> If so what would be the best way to convert over? Change all bulbs over at once or one by one? I was thinking doing it one by one placing a screen just above the water to block some of the new intensity while continuing the normal light cycle. Then start poking holes in the screen periodically to start letting more light in over a couple of weeks of time. What do you think? <I'd make the transfer one at a time, wait a week before doing another. Don't think you need any filtering as we are only going up 150 watts per week. Not a great increase for the size of the tank.> I also just purchased a LUX meter, not really sure why but I heard it was nice to have. <My father-in-law was a gadget man. We called him Inspector Gadget.> Any tips on how to use it and get the most out of it? <Just read the manual or ask the manufacturer.> The probe is submersible so I can check light intensity all the way to the bottom of the tank. Thanks for your help! I want to make sure that I do this right so that none of these animals suffer because of my stupidity! <You are on the right track, Curtis. James (Salty Dog)> Curtis Lots Of Light- Lots of Options! 3/23/06 Wet Web Media Crew, <Scott F. with you today!> I have a 300 gallon reef aquarium. Because of price issues, I have ended up with 8- 175watt 20k HQI metal halides and 8-96 watt actinics for my lighting. The tank dimensions are 96L X 24 T X 36 W. What issues, questions or arguments would you have with this setup versus say 4- 400 watt 10K metal halides? <To be honest with you, it sounds quite nice. However, the electrical draw may be comparable to what the draw would be if you went with the 4- 400 watt setup. My thinking is that the real issue might be the PAR value of the 20K bulbs versus 10k bulbs. If you're intending to keep high-light-loving Acroporids and other corals of this type, you'll get better growth out of the 10ks. On the other hand, I like the aesthetics of 20ks, and you may get nicer colors out of the corals. Having 8 fixtures means 8 bulbs to change, and 8 ballasts to service- essentially 8 things that can fail; 8 more things to keep track of. On the other hand, having 8 different pendants means that you can "put the light where you want it".> Will this lighting be sufficient for SPS coral or clams? <Either will suffice; all depends on your goals- high growth rate versus aesthetics.> This light setup is not really typical for this size tank- it seems- so that is why I ask. Thanks SO much Jason <No problem, Jason. I'd do the math, in terms of energy consumption, and examine which makes more economic sense in regards to your goals. Best of luck to you! Regards, Scott F.> Lighting for a 360 gal I just bought a 360 gallon acrylic aquarium and I am working on the placement for the MH. I have four 250 Watt HQI MHs. << Sounds good, I'd consider 400 watt halides but you should be fine. >> The tank is 6' wide, 4' deep, and 2' tall. << Only 2 feet tall? Then 250 watts should be good bulbs. >> I have read that you should place a MH lamp every 2 feet. So I would have two rows of three lamps for a total of six lamps. However, the middle of the aquarium top is all acrylic. I have read on your website that you should not place MH lights directly over the acrylic and try to place them in between the opens. If I am to do this I would be able to fit 6 lights over the aquarium. My question is this. Should I just have 4 lamps over the openings or should I have 6 lamps and have 2 of them over the acrylic top? << Ooh tough question. I'd probably go with four bulbs at 400 watts each, or four bulbs at 250 watts but add some VHO actinics to go with them. On a tank that size, I'd even consider 6 bulbs over the open areas if you can fit them. >> As always... Thanks for your help! << Good luck, nice sized tank. >> Steve << Blundell >> Kelvin Temp - 1/13/05 I have read your lighting FAQs and haven't seen my particular question. <Then you missed it! It's on lighting FAQ page 3, answer #14, paragraph 2, line 26, letter 47. Just kidding> I have a 225g reef that is 30" deep. I have two 400w HQI Pendants with e-ballasts about 9" above the water. Tank is at 80-81 stable (Night/day). My question has to do with the temperature of the bulbs. I don't have any other lighting and was wondering if I don't have adequate red green spectrum? There is plenty of intensity.... to the point where mushrooms, softies, etc need to be place in the centre of the tank on or near the bottom (two coral head reef setup) for them to open fully. So my question is: Provided you have intense 20k lighting... is it still necessary to have lighting in the 6500, 10k 14k area? <As I am not aware of the species you are attempting to keep, I will provide as general answer as I can...at least for the species commonly kept in this hobby. Most photosynthetic organisms from tropical reefs prefer 'warmer' Kelvin temperatures (5500k-6500k range) as they evolved to utilize sunlight, which is 5500k. However, they are for the most part very adaptable, and should do fine with 20k lighting. They will not grow as fast as they would under a warmer bulb, though> Thank you for your help..... and what a great source of info your site is. It is my primary source when looking at new specimens or problems. Thank you. <You're very welcome - we try!> Scott McAdam <M. Maddox> MH Lighting Hi, I'm planning a lighting system for a 215 gal reef rank. I want to keep some SPS corals, clams, and some softies--a full blown reef tank. I have a PC fixture that will produce about 200 W of actinic light. I'm thinking that I will need about 800 more watts of light.<your figures are correct.> At this point, I think that two 400 W MH lights would be the best way to fill that gap. Please say if any of that sounds like a bad idea.<I would go with three 250's> Since it's a pretty large scale lighting system, I'm obviously looking for ways to cut costs. I'm somewhat handy, so my plan is to buy some pretty good ballasts and bulbs and to build the fixture myself. I wondered if you could recommend one or two ballasts. Can you comment on the 400W Universal Magnetic M135 Ballast -Pulse Start Metal Halide they sell on hellolights.com for $86.00? Any information you could give me about MH ballasts would be greatly appreciated. Should I use 10,000 or 20,000K halides for my application?<10K or 20K, the choice is yours. The Universal ballast will work fine, especially if your on a budget. The electronic ballasts do increase bulb life and intensity. Another ballast would be the "Blue Wave brand". They usually sell for about $100-115 on the internet. James (Salty Dog)>I really appreciate your site and the Conscientious Marine Aquarist, a great resource that I consult often. Thanks very much, Justin Armstrong Metal Halides for now and in the future - 1/28/04 Hi, I currently have a 55 (48x12x20) gallon tank with 440watts of VHO lighting, but I am considering an upgrade to MH lighting. <Very good. Any reason why?> Here is my dilemma. In a year or two, I would like to upgrade to a larger tank with dimensions 60x24x36, <By my calculations (if this is the inner dimension, would be about 225 gallons approximate) so I would like to buy lighting that can be used in both tanks. My plan would be to buy one 250W MH light now, and add a second with the new tank. <Well, if my calculations are correct you will probably want more light than that for the future tank. I am thinking of maybe one 400W now and add or another or maybe even 2 more later.> But I am wondering if 1 bulb is enough in the 55 G tank, and if 250W bulbs are sufficient for the depth of larger tank. <one 400w would be ideal for the 55 gallon with no need for actinic supplementation (unless you want more visual aesthetic balance, which I don't really like myself) but once you move to a bigger tank you will want to add a few more metal halides to maintain intensity and PAR levels> Would 400W bulbs be better in the large tank? <Yes> What configuration(s) would you recommend? <one 10K metal halide for the 55 gallon and three for the 225 in the two 10K, and one 6500. Of course, this all depends on being able to mitigate the heat issue and what type of animals you intend to keep> Thanks, <Sounds good. ~Paul> Dave Aquarium cross braces I appreciate all your support in the
past and am presently trying to solve a problem with my 330g tank. It
is 84"x30"x30" and it is 3/4" glass. When the built
the tank in my home they put two 1/2" glass 14" cross braces
in 14" from each corner. This lead to a 14" opening 28"
opening and then a 14" opening. The problem I am having now is the
left and right halide is directly over the cross brace. This is dimming
the light and I am sure must be changing the spectrum of the bulb.
<Agreed> Not to mention also warming the brace itself. My
question to you is do you know, or know someone that would be able to
help me fix this with problem with smaller braces having to be thicker
or some other solution? <Not smaller... but you could cut the
current braces and move them to the middle of the tank> I know from
what I have read that they should have spaced them out more evenly.
This would have helped to some degree but the braces need to be about
8" wide to really help with the lighting. Thanks a lot for your
help and have a great day, Ian. <Is it worth considering moving the
lights out over the side cut-outs and adding a third (perhaps higher
wattage and temperature) MH to the middle area? Bob Fenner> A Light Conversation... I have gotten great advice from you guys before and now I need some advice on arguably the costliest and most controversial aspect of my new tank. If possible I would really appreciate Anthony's opinion on this subject, but would also like some differing views. <Scott F. here tonight!> Here is my tank, about 2 months into the design process, I figure it will be done in about a year. About 300 Gallon 84L x 24W x 37D. A 7 inch DSB and about two inches of extra space at the top of the tank leave appx 28 inches of water. I don't intend to have the tank filled within a year, like most I see. Rather I will be taking my time and allowing corals to grow, while still leaving plenty of swimming space for my beloved fish. <Great idea!> Only 200 lbs of LR will be used, this should leave me with plenty of room for many years to watch the inhabitants grow. Other than fish this will be a clam and SPS tank. I am not looking for extraordinary growth, but would like to have healthy colored corals and clams that will be beautiful for many years. The clams will not be on the substrate but will be a few inches higher. The remainder of the SPS corals will be at all different heights in the tank. What do you suggest for lighting? My local fish store insists that 2 175 watt 10k Ushios on an electronically moving track will work just fine. As long as I use electronic ballasts (icecap 20% overdriving the bulbs) and good reflectors (sunlight supply reef-optics). I agree that two bulbs will work perfect if on a moving track (thanks for that article Anthony), but I have yet to see an SPS system of this size with this little lighting. <The track concept is an exciting and under-utilized idea, IMO. However, if it were me, I'd go for higher-wattage bulbs, like 250 watts. I use and highly recommend the Reef Optix III pendants with Ice Cap ballasts and double-ended HQI bulbs. They are highly efficient, and really easy to use. I've had great results with Aqualine 10000ks in this configuration, and have been experimenting with some new 20000k bulbs as well. Aesthetically, I prefer the look of 20000ks, but I think that the 10000k's offer the better PAR values> I do agree with him on the use of 3 or 4 T5s with electronic ballasts as supplemental lighting, 420nm, 450nm and possibly their 60/40 for better non-halide viewing. If this set up will work how long should the halides be on for, just 6 or 8 hours, or can I have them on for 10 to accommodate better viewing? <I would go with the full 10 hour photoperiod for all of your lights. In my opinion, there is no real advantage (other than energy consumption/heat issues of burning the halides for a shorter duration.> If you think that this is too little light how about 2 250 HQI 10k in a Reef Optix III, electronic ballast, on the same moving track? <That's my recommendation> I think it would be great if 175s would work, save me money up front and ongoing. <Again, in my opinion, the cost differential between 250watt HQI's and 175watt mogul bulbs is not that great, particularly if you're using an efficient electronic ballast, like the Ice Cap. And, I think that you will see the difference in your coral growth over time.> But I also really want all of the SPS corals with the bright pigmentation, and want Maxima clams. <Yep-go for the 250 watt bulbs.> Thanks again for all your hard work and experience. <My pleasure! Hope this helps. Please let us know how things progress. Regards, Scott F> Acrylic Tanks and MH Lighting We are in the investigating process of the "big tank" (650 gal). We want to leave the top open and use metal halide pendants for lighting since everything except the viewing window will be behind the wall. In one of the quotes for a custom tank the dealer said the tank has to be glass because the metal halides will destroy an acrylic tank. I have never heard this before and we had really decided that acrylic was the way we wanted to go. Is there any truth to this? Thanks in advance for your help and for the MANY questions that will be coming your way in the next few months. Beckie <No truth to it as far as I'm aware... Our old companies installed hundreds of acrylic tanks with metal halide lights in them... Bob Fenner> Acrylic Tanks & MH Saw the post about MH and acrylic tanks. Just wanted to add that most acrylic tanks leave a considerable amount of acrylic in the top pane for structural support. A MH placed directly over one of these acrylic struts will likely cause that to crack. <Ahh, yes... Needs to be offset, and even then, suspended per manufacturer's recommendation... per wattage, a good distance above the top> But as long as the bulb is over a cut-out it should be fine. (I'm speaking from personal experience: I cracked one of my struts with a misplaced MH bulb. Others have traded thin acrylic panes on standoffs as heat shields; not sure if this works.) <Me neither. Likely not absolutely> A professional acrylic aquarium craftsman also warned me that the normal practice of polishing the top pane in order to round the edges of the cutouts can result in "crazing": a network of fine surface cracks that can, over time, develop into a real problem. MH bulbs might make any potential crazing worse. He bevels his edges rather than polishes them to reduce the risk of crazing. Marc <Good input. Thank you, Bob Fenner> One MH light over reef... enough? Hi: I am in Cochin Kerala India near the Southern tip of India. <cheers my friend from afar> I have a 7ft by 2ft by 2ft marine aquarium. It is lit with one 150W MH 10000K. I have also put some 4 15 W actinic tubes and a 30W & a 20 W daylight tubes (they are on both sides of the MH. But I feel that lights at the end are not enough. What's your opinion? <Indeed... it is not enough light if you wish to grow coral along the entire length of the tank. But you can still avoid extra MH lamps by strategically keeping low light corals and decorative algae on the lower light flanks of the tank while placing the more demanding corals directly under the MH> The MH is HOT in Hot tropical India. I cannot, as of now, afford a chiller. <understood> I wanted to get some 36 W 10,000K CFLs (two to be on either end. But I do not know where to get them. I searched the web for any seller in India and the search was negative. Have you any idea where I can get them in India? <not sure where you might find them in India, but for any such aquarium hardware you seek, I suggest that you contact the manufacturer and let them earn your sale <G>. They can direct you to the closest distributor or a mail order outlet. With kind regards, Anthony> MH lighting vs. PC lighting Bob, I have just finished reading the articles on lighting posted on your website. I still have a couple of questions relative to this subject. I have a 300 gallon fish/invert system. The tank measures 96x24x24. <This is more a 240... a stock shape system in the trade... about 231 cubic inches per gallon...> I am currently using 2-400watt MH and 2-175W MH bulbs to provide lighting for the fish, leather corals, mushrooms, polyps, anemones, and some LPS corals. Of course I have the usual problems of excessive heat, and ultra high utility bills. <I do understand this!> Could I successfully convert my lighting to PC's and still have my animals thrive? <Yes, in all cases... even if you have high-intensity light species like tridacnids, many SPS corals, they will do fine, some better under CF lighting... in a twenty or so inch depth of water system> Would it save me on my utilities and heat gain? <Absolutely, on both counts> And is there a table or matrix available to determine how many PC's and what size (wattage) they should be? <Maybe somewhere... haven't looked for recently... Take a look at the links to lighting manufacturers on the www.WetWebMedia.com site> Thanks for your input. Bob McCook <You're certainly welcome. Bob Fenner> Lighting a very deep captive system Mr. Fenner, I am in the
process of purchasing a rather large aquarium. One 84" in
depth. <Wowzah, this is a TANK!> The company supplying the
tank, Reynolds Polymer, claims that it is impossible to maintain live
rock at such a depth and wants to sell me a fiberglass reef. <Hmm,
well... my or an actual rebuttal might be that "live rock" is
found in the wild at much greater depths... But having another tank
tied in... is a good idea> My question is, what type of lighting,
what K and wattage, and what spacing is necessary for the successful
maintenance of a Fiji Rock reef. No corals etc, will be part of the
reef. Any help will be greatly appreciated. <10,000 to 20,000 K for
the very deep system... something above 5,000 Kelvin for shallower...
wattage for the big tank in the 1 kilowatt size... the smaller, down to
175 watts, to 250 to 400... Much more to talk over my friend. Please
take a look on our site, particularly the articles and FAQs on custom
tanks: http://WetWebMedia.Com/tksstds.htm
http://WetWebMedia.Com/dessysart.htm Bob Fenner>
Acrylic Tanks and MH Lighting We are in the investigating
process of the "big tank" (650 gal). We want to leave the top
open and use metal halide pendants for lighting since everything except
the viewing window will be behind the wall. In one of the quotes for a
custom tank the dealer said the tank has to be glass because the metal
halides will destroy an acrylic tank. I have never heard this before
and we had really decided that acrylic was the way we wanted to go. Is
there any truth to this? Thanks in advance for your help and for the
MANY questions that will be coming your way in the next few months.
Beckie <No truth to it as far as I'm aware... Our old companies
installed hundreds of acrylic tanks with metal halide lights in them...
Bob Fenner>
|
|
|
Features: |
|
| Featured Sponsors: |
