FAQs about Ultraviolet Sterilizers 1 Back to Articles on: Ultraviolet Sterilizers, Physical Filtration, Ultraviolet Sterilizers in Pond Filtration Related FAQs: Ultraviolet Sterilizers 2,  Ultraviolet Sterilizers 3, Ultraviolet Sterilizers 3, UV Use in Business Set-Ups, Rationale/Use, Selection, DIY, Installation Issues, Operation/Maintenance, UV Lamp Replacement, Repair, Bank of ganged Ultraviolet lamps at Quality Marine, Los Angeles. This is a Vectron unit by TMC (Tropic Marine Centre) of the UK.

UV Question 7/17/05 Hi, I have a quick question of what you think about the comparison between RO, DI, and UV sterilized water for a saltwater tank.  I know that RO is the best for any saltwater aquarium but I was wondering how RO or DI compares to UV sterilized water? <... compares in what way? Ultraviolet sterilization of water of poor water quality will do nothing to improve it> Also we have well water and a UV light attached to the well (not the aquarium) already, and I know both the positives and negatives of having a UV on an aquarium and I was wondering what you think of have a UV light sterilizing the water before it goes into the aquarium? <... of dubious value... the addition of salt mix to water that has some biological addition will likely kill off most all microbes> (Will this help at all with preventing any algae problems) Thanks for all of you help! <Will do nothing to change the potential for algae growth. Reverse osmosis, deionization are techniques that remove dissolved solids, gasses themselves... You might read re all three... on WWM. Bob Fenner>

UV tank problem 7/6/05 I recently put a Jebo 13 watt UV light on my tank (using a 100 gal. Stock Tank) and now the sides and bottom of tank has a Black soot like covering on it. Also the inlet and outlet tubes from the U.V light box,( which is black). What is causing this and any help at all would be greatly appreciated? The water is clear now with the light, checked light and it is all clean but inside the case seems to have some black that will come off too if rubbed. Thanks for any help you might be able to give. <<I suggest you contact the store where you purchased it, or contact the manufacturer directly.  Sounds like the housing is reacting to the UV light.  James (Salty Dog)>> Billie Allen Protein Skimming, Ozone, and UV Use in Marine Filtration 7/5/05 Hello Bob, I enjoyed your article on ozonizers on www.about.com. <Actually on WWM... a link on about.com> I have a quick question for you and don't want to take too much of your time but I would appreciate your opinion. I have a 240 gallon reef with a large population of SPS and LPS corals. With the introduction of ozone to have my protein skimmer at its peak efficiency would be great. But would the introduction of ozone into the contact chamber of the skimmer kill even the beneficial microbes along with zapping bacteria, microbes and unwanted organics? <Oxidizes all indiscriminately. What most folks shoot for is "enough" O3 to reduce free-living bacteria (most ones you want are not suspended in water) and organics...> You stated in the section where you discussed the cons of using a UV Sterilizer that one of the cons of using a UV sterilizer is that you also zap beneficial microbes as well as bad. <Yes... to some extent> In a reef aquarium my corals rely on a lot of the plankton and microbes for food. Would the ozone affect this and is there any recommendations you can suggest on the usage of ozone? I look forward to your advice. Thank you, John Vu <In practical application John, folks have little lingering ozone... providing a few hundred milligrams per hour, delivered to/through your skimmer directly or not, will not harm your livestock. Bob Fenner>

Jebo 13w UV sterilizer Good evening: <Mornin'!> I just purchased a UV sterilizer by Jebo 13w.  I purchased it off eBay it said it is new but did not come with directions or hoses.  I am brand new to saltwater.  Would you be able to help me hook this up? <Think so> Does the sterilizer go into the aquarium or on the outside? <Out> If on the outside is it suppose to sit on the ground or attach to the tank. <Either way... better to "mount" on the floor or steadily on the wall, stand... where the hoses won't get pulled on, but you can reach to check out, do periodic lamp replacements...> Does it matter which end goes to the submersible pump? <Nope>   The other end I would assume goes into the tank. <Yep> I tried asking the person I purchased it from but they have been unable to help.  I look forward to hearing from you.  I attached a pic.  Thank you for your time. Brenda <Ahh! My sisters name. Bob Fenner>

UV troubles? 7/23/05 I just purchased an 18 wt Jebo UV filter for my 55 gal. saltwater tank. Is the bulb supposed to go on and off or stay on continuously? <The latter> One side of the filter stays on dimly at all times the other comes on real bright stays on for about 1-2 minutes and goes off again. Is this normal? Nightmare <Mmm, I suspect this unit may be defective... such devices usually have a starting mechanism... that shows the lamp brighter during the "turning on" phase. I would take, send this product back and ask the manufacturer to take a look at it. Bob Fenner>

U.V. sterilizer addition value You guys have helped answer lots of other questions, so I hope you don't mind another. I've been thinking about adding a UV sterilizer, but I'm not sure it's worth it. I have a 55 gallon, with 3 inches of sand/crushed coral, a few hardy fish (some damsels, algae blenny, red Coris wrasse), about 12 pounds of live rock (I know not nearly enough, but will increase as soon as I upgrade to sufficient lighting), and a few inverts. No live corals. I've had some ich problems in the past (all is good at the moment), but I'm still almost afraid to add new fish. I've read many of the articles on the site regarding both ich, and UV sterilizers and I see that UV sterilizers are certainly not a guaranteed means of killing parasites, especially in tanks with a sand substrate.  For new tank additions I'm thinking of permanently setting up a basic 10 or 20 gallon quarantine tank with no substrate and a simple whisper power filter... <A much better investment> ...and maybe keeping a fish or two in that simply to cycle and keep the biological system running. If I use that setup as a quarantine, am I wasting my time with a UV sterilizer? <Mmm, not wasting, but U.V. is not a cure all...> I do see that free floating algae is killed off relatively easily with a sterilizer, and was thinking I should get one for that purpose, but I don't want to spend $100 or more just for that. <Plus the electricity to run continuously, replacement lamps...> Are the cheaper ones (I can get, for example, a 9 watt or 13 watt Jebo ) sufficient for that purpose, and will they help at all to control parasites, assuming the flow rate is proper (I understand it should be roughly 20 gph per watt)?  <Small wattages, slow flow rates... will only help marginally> Finally (am I pushing my luck?), the tank is up and running about a year, with wet/dry trickle filter and a faulty protein skimmer (I'm likely to add the AquaC Remora soon). <And this would be a MUCH better investment> Water quality is good, but the water is not crystal clear. Would I benefit from removing some or all of the bio balls at this point and adding a significant amount of carbon in place of the bio balls? <Possibly> Or would I be better off leaving as is and adding a small canister filter, like a Fluval 304? Thanks in advance.  Best Marine Aquarist advice anywhere! <Many things to consider... if it were me, knowing from here what little I do about you, your system... I would invest in a quarantine set-up number one... upgrade your skimmer secondly, and if you have/had more money to put into your tank, lastly of these three considerations invest in an ultraviolet sterilizer. Bob Fenner>

UV Sterilizer <<Greetings, not Bob but JasonC...>> Hi Bob I really enjoy the website. Just a quick question though. I just purchased the 9 watt custom SeaLife UV Sterilizer. It looks like the water goes through a coil tubing around the bulb. <<Ahh, this the Helix, the new UV unit from CSL, I presume.>> What should be done to maintain this product in the future to maintain its effectiveness (cleaning, bulb replacement, etc)?  <<Well, replace the bulb as the manufacturer suggests, that is a good place to start. Then cleaning, may not actually be needed because the aquarium water doesn't actually contact the bulb. Again, I would stick with the manufacturer's directions.>> Thanks for the help! <<Cheers, J -- >>

UV Sterilizers Thank you for your prompt response to my earlier question. Do you recommend Custom Sea Life or Aqua Ultra Violet UV Sterilizers? <I do not really recommend any UV's. Far cheaper and more effective to focus on excellent husbandry. If you want, ask around the various chat forum, message boards, or local aquarium societies for recommendations for your fellow hobbyists. -Steven Pro>

UV Fixtures I have just started a saltwater fish-only aquarium. I have bought a Custom Sealife double helix UV (38 watt). They say that the longer the exposition to UV is the better. My problem is with the water flow rate. They recommend between 100 gph and 500 gph. What rate should I have for the UV to be the most effective. <The slower the flow rate, the greater the kill rate and number of things killed. Speed translates to contact time. It is comparatively easy to kill free-floating algae. The next hardest (requires more contact time) is free-floating bacteria and lastly is parasites.> Also how many hours a day should I leave it on. <24/7 for maximum effectiveness.> Thank you, Jean-Yves From Montreal <You are welcome. -Steven Pro>

Ich solution Dear Bob, Guess that I would like to share my experience. I've went through 3 bouts of ich problem throughout the whole of last year and lost the whole batch my prized angels and BF's. Water changes, medication and whatever nots did not help. My friends suggested copper, not possible as I've got LR and Soft corals. I did not consider UV as many friends claim it does not work and problems in cleaning the plastic sleeve periodically. About 4 months ago, I noticed that my LFS store installed fluorescent fixtures in the sump with special UV germicidal bulbs. I was cynical at first as I always thought that the water has to be within a few mm away from the bulb for it to work. In this case, the distance was more than 8 inches! For the next 10 days or so, I noticed a marked improvement in the loss of new arrivals and also reduction in algae formation on the glass. I've no choice but to try this method. To this date, almost 3 months now, my angels are still alive and kicking and no sign of ich. The bulb I use is only a 18W Philips TUV FL (in the sump )or an equivalent that is Sankyo Denki. Please note that both bulbs are rated as germicidal and do not look too long into the lighted bulb as it may cause blindness. <Yes> My tank is a 200G and for the first few days, it was switched on for 24 hours. Now, I leave it for 12 hours only.. I have no explanation to this but who cares, it worked for me and I would like to share it. <Thank you for this. Will post for others edification, consideration. Bob Fenner>

A Few Quick Questions (lionfish, UVs) I just added a lion fish to my tank that is full of inverts. The only one am scared he will eat is my cleaner shrimp. So far he has been fine with the shrimp and seems to be begging the shrimp to clean him. I have seen them face to face and the lion did not eat him. What do you think about this situation. <Sounds good now, but no telling if things will change later.> The lion is also the only fish in my tank because all the others died two weeks ago from ich. My fish store told me that after a few weeks the ich would be dead. Is this true? <More likely one month and you are safe.> Are lions pretty good about not getting diseases? <Hardy individuals, but will succumb if exposed and difficult to treat.> I also would like to add a U.V sterilizer to my 46 gallon tank. What size do you think I will need? <Varies by manufacturer.> Will it help in the prevention of diseases? <Somewhat, but not nearly as effective as quarantine and proper husbandry.> Last question is about bristle worms. I have some very small bristle worms in my aquarium they seem so far not to have done any harm. I have read that having some worms can be beneficial to my tank. What do you think? <Yes, almost all are beneficial.> Thanks for your time and I love the site keep up the good work. <Thank you, Steven Pro>

UV sterilizer I have been working with saltwater and freshwater fish for two years now. Currently I have a 46 gallon bow front aquarium with a emperor 400, Prizm skimmer, and a VisiTherm heater.  <do upgrade the skimmer as soon as possible (before buying next fish/coral)> I also have about 15 pounds of live rock and some invertebrates. all my fish died from ich) Through the years I have had success and failure and really want to get the failure to go away. I have had the most problems with my saltwater tanks and have learned many lessons in the process.  <hopefully quarantine all fish for 4 weeks without exception was one of them <wink>> I have two questions I have been trying to get answers to for weeks now. The first is do you think I need to add a medium sized canister filter to my tank.  <nope... a fishless invert system would benefit by far with more rock before it would a canister filter> The second question is a little more complicated. I have just purchased a 30 watt U.V sterilizer for my tank with a Rio 1600 powerhead to run it.  <a huge UV for this tank and the water pump is too fast/strong for effective kill time I suspect (consult mfg recommendation for flow rates)> I haven't hooked it up yet but is 30 watts too much for my sized tank. <not too much... but larger than necessary. No harm though> I got a good deal on it and I hope it will keep the parasites off my fish and reduce the algae problems I have been having.  <you will be disappointed about the fish part but delighted about the algae control. UV filters can only kill free-floating parasites... but if you do not QT a fish and bring one into the display with parasites on the body, then they stay there, drop off and some jump back up onto the fish without ever passing through the UV. UV filters have a very strict range of terms under which they will control pathogens... do review archives and FAQ's on this topic (especially recent FAQ's). Any tank with gravel or sand will be difficult to control parasites in if you make the mistake of not QT them> Do U.V sterilizers really help with these problems.  <bulb must be less than 6 months old, water flow slow, water crystal clear and prefiltered (carbon weekly ideal), etc> Thanks for your time and I hope to hear back from you soon. <best regards, Anthony>

Best Use of a UV Robert, <Steven Pro this afternoon.> Hi again. I just purchased a 30 watt UV sterilizer for my 180 gallon fish only tank. Before I set up the UV unit I would like to know a few things first. For a 30 Watt 36" bulb, what is the recommended flow rate for killing Protozoan Ick and other parasites? <I would use your manufacturer's recommendation.> How many gallons per hour pump & what model should I get. <Get a pump rated for just under the manufacturer's maximum flow rate and please prefilter the pump.> Where do I place the pump, in the tank or in the main sump? <The sump would be better; water cleaner, less of an eye sore, etc.> Do I collect the water from the main tank or one of the sumps? Do I return the water directly to the tank from the UV or back to one of my sumps. <To the tank or the other sump as long as the water is moved about.> I need to know the most effective way. THANKS! <You are welcome. -Steven Pro>

Re UV: I have been told the best placement for the pump to the UV is about an inch or so above the substrate because that is where most of the pathogens reside. This 50g with the Amyloodinium is a Uniquarium. There is a separate filtration area behind a false back. Water from the front display area overflows into the back, thru the filtration and returns to the front of the tank on the other side. Would the UV be just as effective if the pump were to be placed in one of the back filtration areas? <In practical application, yes> Re nutrition in a Q tank: You said "Sorry for the ambiguity. I mean/t soaking in a vitamin preparation, iodide solution and possibly HUFAs (highly unsaturated fatty acids)" What vitamin preparations or HUFA preparations do you recommend? <Selcon, Micro-vit... ones you can make yourself> Re iodine: What is the purpose of iodine? <An essential nutrient for many forms of life, as a disinfectant, "immune system booster"> Under what circumstances and conditions do you feel it would be warranted? <Regular administration (weekly generally) to system water, to foods daily in some applications (treatment, aquaculture)> Which iodine preparation would you use? <Potassium iodide. Am not a big fan of Lugol's> How much? How often? <Mmm, much to state here... "measurable" next day by experimentation is my best response... w/o launching into a necessarily at-least-article-length monotribe of what is involved> Re: Nutrition in general: Would any or all of these supplements be a good addition on a regular basis? If so how often? <Mmm, yes... some daily, others more like weekly... vitamins in particular> I read about Vitamin C supplementation on the site. How much and how often would you recommend the addition of this? Does it have any effect on water quality? <Daily to weekly... as with humans, not much downside to "over-supply". No practical consequence to adding to aquarium water quality unless unrealistic amounts are added> Thank you again as always, Leslie <Thank you my friend and fellow aquarist, lover of life. Again, my apologies for the delay in response. Bob Fenner>

Re: Seahorses, Aquatic Nutrition, UVs, WWF Chatforum Hi Bob, <Hello. Sorry for the delay in response. Have been away> Thank you for the responses to the questions in my last e-mail. Now in response to your question....... >How would you improve it?> I would like to see more species specific information for instance recommended temp ranges, size, minimum tank size, ease or difficulty of care, diet, availability in the hobby, reef safe, and any other tid bits tips or hints relevant to keeping the fish. I am a director on seahorse.org responsible for moderating the basic, tankmate and general forums. I refer to your site frequently for information needed to assist with my responses to posts. <Good ideas> Please do not take this the wrong way, but the information presented on seahorses seems dated to me as is much of the information currently available. Thank goodness for the Horse Forum column in FAMA. <Yes, dated and better source> I am so looking forward to your contribution. There are also a couple of books currently in varying stages of the publication process. One by Pete Giwojna. <Ah, a credible, lucid source> The advent of captive bred seahorses has made keeping them healthy, happy and thriving in captivity a reality. They are so much easier to keep now. <Immensely so> They were my first marine aquarium experience over 3 years ago and I would have never considered the possibility prior to Ocean Riders. Despite my problems in my other tanks I have done very well with the horses. I have actually found them to be easier than other marine fish or many of the FW fish I have kept. Please forgive me if you are aware of any of this information. There are 18 species currently being bred by 3 commercial aquaculturists, Ocean Rider which I have noticed mention of on your site a few times, Tracy & David Warland of South Australian Seahorse Marine Services, and Ocean Oddities. 7 of the species are available to the hobbyist, at this time, from either Ocean Rider or FFE for between 39 and 150 dollars. The available species include, kuda, erectus, reidi, abdominalis, whitei, barbouri, and procerus. The additional 10 species are soon to be released, in the next year or so. FFE has also said they are expecting some CB pipefish any time now. The seahorses all readily accept frozen foods and are actually quite hearty and disease resistant. Most of us feed Mysis relicta, a completely freshwater species of Mysidae, manufactured and prepared by Piscine Energetics @ www.mysis.com. Are you familiar with the product? Many of the seahorse.org members are new to marine aquaria. They have been quite successful with seahorses and their appropriate tankmates. So, I would like to see more current information on seahorses that pertains to the CBs available now. <Thank you for this important information re Hippocampus husbandry> Karen Etling one of my esteemed seahorse.org curators is writing an article for your site I understand. I think that is great!! Chris Burns and Pete Giwojna both have written several articles maybe they would be willing to share them on your site for the seahorse enthusiasts. <We greatly welcome these inputs, links or other access to their ideas, discoveries> I recently posted in the chat area. I think that an edit and delete post option, available only to the moderator or author of the post once it has been posted, would be helpful. <Will send this note on to Zo for comment> I find the format of the FAQ's and question/answer areas a bit hard to read for me personally. For me, the information would be more easily read if the answers to the questions were separated out from the text of the letter some how......maybe another color, font. or indented? <An excellent idea... we simply have not had time to do much editing of this content.> I do like very much that the questions are ALL answered as they are asked, and as a result nothing is missed, a function of the format I am sure. <More so of commitment on all our behalf> There was one place I noticed where the questions and the answers were in more of an alternating paragraph style. I found that easier to read than when the answers were inserted into the text of the letters. <I see> I really like the lighthearted way in which information is presented and questions are answered, It is very nonjudgmental and non-threatening. I am sure you guys are all much busier due to that. I know it's a lot easier for me to ask when my questions are answered so promptly in the previously mentioned manner. I am actually quite embarrassed about my errors, but was never made to feel bad about it by you and your staff all seem to respond in a similar nonjudgmental and non-threatening manor! Very important qualities IMO for learning to take place. <For all of us> That's all I can think of at the moment. If something else comes to mine I will send it your way, if you like. <Please> I have a few more questions if that is OK? <Certainly> Re: Leaving my tank fallow: Should I be changing the water and stirring and/or vacuuming the sand, during the 3 months it is fallow? If so how much would you recommend and how often? <I do encourage vacuuming during these times... on your "regular schedule", perhaps weekly to monthly per: http://www.wetwebmedia.com/water.htm> Do you have any suggestions for removing the residual greenish yellow tint, of the water, from the Greenex and Acriflavine? Prior to adding any new life I did several 100% water changes. I have used carbon and PolyFilters. <These are exactly my M.O.s> Re: a Jawfish, Opistognathus rosenblatti in particular I currently have a 0 grain size substrate in the tank along with some small shells and coral rubble. What would be the appropriate sand grain sizes to mix? <About one quarter the larger material, mixed into the upper range of the whole blend... will become more mixed with time> I am considering a tank for abdominalis, whitei and breviceps which are currently being bred and maintained by Tracy & David Warland of South Australian Seahorse Marine Services  <Met these fine folks at last years Aquarama in Singapore> in the same system at 71.6 degrees. Would 71.6 be to low to maintain one? <Is fine. The Baja species is found at this and quite cooler temperatures... the others reach comfortably into this realm> In reference to Jawfish recommended as seahorse tankmates on seahorse.org, you said "Most of the commonly available species, agreed" I wasn't quite sure from your answer if you would consider Opistognathus rosenblatti one of the commonly available species and thus appropriate for a seahorse tank? or better to choose another species? <O. aurifrons would be better. The larger species will likely prove to be too aggressive feeders to be kept with Hippocampines> I know they are usually pricey, but I see them offered much more frequently online these days and occasionally in the LFS.

Why won't my UV kill Ich? My entire tank (except for two, maroon clown and wrasse) has ich. I've started using formalin and fresh water dips last night. I've turned the skimmer off but have left the UV sterilizer running. . . is this the right thing to do?  <excellent and just short of perfect without moving everyone into a bare bottomed QT tank> I've considered using Greenex or copper along with the formalin -- do you recommend this?  <rather hostile.. only if necessary. The formalin should be enough> If caught early enough (they are still acting fine, eating good) is ich curable?  <yes... very much so. Can be cured without medication actually with fish in a bare bottom QT tank and faithful daily water changes from the bottom for 8 consecutive days to siphon out tomites of parasite and break its life cycle> Should I still feed them every day, including vitamins? <very important!> I don't understand how I can still get ich -- that's what I bought this UV sterilizer for. . .can you provide an opinion?  <UV sterilizers do a terrible job of preventing Ich. You money would have been much better spent (and less of it) on a hospital tank that all new fish go through first. These quarantine tanks (QT) prevent Ich from entering your display through faithful screening and treatment. ***The problem with a UV sterilizer for controlling pathogens is that they have a narrow range that they will work in. The UV lamp must be less than 6 months old, the water MUST be prefiltered of all particulate matter (sediment free), the tank water MUST be crystal clear (heavy frequent use of carbon else discolorants reduce efficacy of UV light), the UV chamber must be frequently cleaned of sediment and organic slime buildup inside or light is blocked (just look at how much slime builds on power filter tuber in one month), the water flow must be rather slow as per mfg rating for kill time and the bulb must be sufficiently intense to handle the rate of turnover for the tank. And even after all of those things have been satisfied, it can only denature the parasites that are run through it... some may travel through the water and attach to fish without ever traveling through the UV! For disease control Ozone is easier, much more effective but easier to abuse. My vote is always for a QT tank for all new and sick fish> Is the sterilizer helping at all?  <I doubt it if you weren't advised of the above and stay on top of it> Also, my water quality is excellent, I haven't added any new fish in two months, and there have been no changes (new rock added, etc.) to the tank. . . what caused this ich??? <temperature changes are the most common reason (drops or fluctuations between night and day). Very common in spring and fall seasons when house temps fluctuate with seasonal swings and doors and windows opening and closing> Thanks for your help. . .I'm trying not to get too frustrated but this hobby is TOUGH sometimes!!! :) <your just not drinking enough <wink>. Anthony>

REDOX, O3, & U.V. Bob,  I was curious if you could point me in the direction of a source regarding the output of O3 from a U.V. sterilizer in closed systems? I know the amounts would be trace but I'm curious as to its over all effect on REDOX and dissolved oxygen.  <Wish I did have a ready source or lead here. Both redox and D.O. are improved by U.V. ozone generation... and the amounts of O3 produced by some U.V. units are appreciable. I would contact the actual manufacturers of the units (a few links on the WetWebMedia.com Marine Links, General Links pages) and ask them in turn if they could provide you with references. Alternatively you might run on over to a large college library, ask someone to help show you how to do a computer search (in the science, technology library/section) as: http://www.wetwebmedia.com/litsrchart.htm Lastly, you might well want to do your own experiments here... using different samples of water, times, turning the U.V. on/off, measuring the values you're interested in. Bob Fenner>

Ozonizer or UV sterilizer? Hello again! <Salute! Anthony Calfo in your service again> This time I need your advice about the next step I should make in order to be more "conscientious" (I got Bob's book just yesterday - ordered it from Amazon.co.uk). As you can suppose, I have neither an ozonizer nor a UV lamp. <not necessary but sometimes quite helpful> My marine aquarium is 210 liters (approx. 55 gallons) and is fish-only (for the time being!). I have an Eheim external biological filter (not a wet-dry one) and an Eheim internal sponge filter (I replace the sponge with the Eheim activated carbon for two days a month - is it ok?) , <you certainly can treat with carbon for a longer period of time, even full-time for optimum water clarity> a two-way internal protein skimmer  <do adjust so that it can produce dark skimmate daily> and an electrical circulator. I used to have an undergravel filter but I was told that it makes no sense to keep it since I have an external biological filter, so I took it out. Ammonia is 0.0, Nitrite is 0.0 and Nitrate is 100 mg/lit (maximum of the Tetra test kit!). My Blue Tang has already been through twice a fungus disease and once Amyloodinium. I am told that the installation of a device will help to avoid some of the diseases... What will be my best choice to start with? I have been told that for a small system like mine the best is to get a UV-lamp.  <definately safer, although not a guarantee to prevent diseases. For that, a quarantine tank for all new fish or occasional sick fish would be better> Some of them are fix - their lamps are not replaceable (I have been told).  <if so please avoid these models> Which one should I buy? Is the Tetra UV lamp reliable and good quality?  <a good reputation/brand. Do be sure to buy a model with a quartz sleeve for easy to replace bulbs.> Which size?  <in American wattage, a 15-25 watt unit for your tank> I really do not know. May be too many questions (sorry!) <no worries at all, my friend. Anthony Calfo>  Best regards, Thanassis (your Greek friend)

Ozone & U.V. I told you I had a two part question but couldn't think of a great way to formulate it. I've read your book and perused WetWebMedia looking for an answer to a specific question about ozone. I want to start using it in small amounts in my Top Fathom TF300 skimmers. If any residual ozone is passed through a U.V. sterilizer will it be destroyed or converted back to standard oxygen? <You can do experiment/s to ascertain this yourself... mainly it will pass through and be added to by the UV's action> We are talking about the small amount generated by the tiny "Coral life" brand ozonizers set to low. No output level was stated in the destructions but I have noticed a major performance boost in the skimmers the few times I've used it. My concern is ozone getting into the main tanks and rotting the rubber O rings on my bulkheads? Ozone is an after thought so I never checked to ensure these gaskets were U.V. resistant. <Ah, not a problem. Very little ozone involved, almost none that gets as far as the tank itself. Bob Fenner>

UV Sterilizer Mr. Fenner, <fish buddy Anthony in your service> This is my first time writing in, I spend most of my time reading everyone else's questions. <a very good way to learn> I would like to know if I should remove the bio balls and floss from my canister filter I am using to run a UV sterilizer?  <please do not... they are unrelated and do not conflict> I have a 125 gal. salt tank (fish only) and I have a wet/dry with media in it already. Also the canister pump is an old Eheim 2213 do you know if it is ok for salt water? < indeed... could be handy> Thanks for your time and an excellent web site, <quite welcome. Anthony> Gavin

Copepods and UV Sterilizers Hi, Will running a UV sterilizer kill beneficial copepods and amphipods? <If it is powerful enough, the flow rate through it long (time-wise) enough, yes> I had a large bug explosion a few months ago so I got a dragonet and he was eating like crazy. Now, he still looks like he's constantly picking through the rock and sand, but he is getting skinny as if he can't find enough to eat. I'm thinking about setting up a refugium under the tank and getting a amphipod breeding mat and starter culture from Indo-Pacific, but want to find out why the visible bugs are gone? (Still see larger bugs from time to time.) <Likely consumed by the Mandarin/Dragonet... they can/really mow through such fauna. I do agree, urge you to go ahead with your added sump/refugium plans. Many benefits, much fun. Bob Fenner> Thanks for your time, Michael

UV 1 Clarifier Hi Bob, How are you today? We had an ice storm here in MD yesterday and things are getting back to normal. Here is the response I got form Tetra about the unit. I also called Aquanetics and the bulbs they had they weren't sure if it would fit my unit, plus they were not familiar with my unit. I am thinking I may need a get a new unit, since getting bulb seems to be hassle.  <Perhaps for the best> It's a shame though as this unit is on a year old. <Did you try contacting who/where you got this product from? Are there any identifying names/manufacturers on the product, its components?> If you have no other suggestions as what I can do and I have to get a new unit what make and model do you recommend for a 125 gallon. <Depending on fluid-moving source, capability, 20-40 Watts... my first choice are the TMC units (Vecton)... though hard to come by in the U.S., some input: http://www.wetwebmedia.com/tmcpropc.htm Next choice are the Emperor Aquatics units... at any length, do get a quartz or Teflon-sleeved unit, with a remoteable ballast... Do seek the opinions of other aquarist end-users: our chatforum: http://talk.wetwebfotos.com/ re actual recent use of products, choices.> The sweetlips is coming along, I'm still praying and kind of preparing myself for if it begins to deteriorate. Thanks for what has begin to seem like daily advise. Gillian <Be chatting and investigating my friend. Bob Fenner>

Re: Update on UV 1 Hey Bob, I contacted Tetra and they said the other bulbs would be too big for the unit. I kinda figured,  <I as well> but any way any suggestions as to what I can do? <Run the unit with just the under-powered lamp... some improvement is worthwhile, attainable here> My concern is I am not sure if the unit is working as effectively as it could as a UV sterilizer, and I was thinking after reading the FAQ that maybe due to the lack of wattage that the reason for the reoccurrence of ick. <Oh. UV sterilizers of and by themselves will not prevent or cure ich...> Now I know that the UV sterilizer does not prevent ick, but is suppose to help control it. So I have had it for a year now and it's time to replace the bulb. Any advise?.. Thanks Gillian <Do replace the existing lamp with another of the same size/wattage and use. Bob Fenner>

Re: Update on Sweetlips and UV 1 The guy I spoke to said there was no bulb available that would fit that unit. Ideas as to where I can find a bulb for this unit? <Yes. Try Aquanetics first: http://www.aquanetics.com/> What do you mean by "just the under power lamp"? Please explain. Gillian <Just using the low wattage UV lamp that goes with the present unit. Bob Fenner>

Update on Sweetlips and UV 1 Hi Bob, Hope all is well with you. I just wanted to update you on my progress with the sweetlips. Well like you advised I moved the fish to a copper free environment, my main tank, it has been about five days now. After the first day or so the fish still would not swallow any foods but put them in it's mouth. As of Sunday it started eating again, regular frozen formula for dinner and some pellets for breakfast. <Ah, great> It had about 70% of it's usual diet for dinner last night and accepted pellets again this morning. I am very happy as it was beginning to show signs of weight loss. <A bad sign with these fishes (plectrorhinchinines... don't try to say this three times fast) as you know> I have began soaking all foods at every feeding to help gain his weight back. So hopefully nothing changes, thanks for the help. By the way I am finally a believer I ordered a copy of your book last night after getting rave reviews, so hopefully in a couple of days I'll be getting it, I'm excited.  <I as well> I was reading the section last night on WWM about UV sterilizers, and I have a question. I currently have a TetraPond GreenFree UV1 Clarifier, they are used in ponds are you familiar?  <Yes, quite> Well It recommends the usage of a 9w Phillips bulb. After reading the FAQ, I realized that for my size tank a 125 gallon, you recommend the use of a 20-25w bulb, do you think I could change the wattage of the bulb and have the unit still function. I mean will it cause a overheating, or for that unit that's as much wattage as it can take. <Worth investigating... the "kill rate", flow of water, suspended solids... many factors go into how effective an ultraviolet sterilizer is in a given application. No worries here re overheating, melting of fixture... but unlikely other wattage lamps will fit the fixture.> I notice tetra also has UV 2 & 3 bulbs, would one of those bulbs fit my unit.  <Perhaps... do contact them, ask. They do have a nice website: http://www.tetra-fish.com/> Thanks for advise on the sweetlips I look forward to reading your book.. Gillian emailing from work today. <Be chatting my friend. Bob Fenner>

Re: Update on Sweetlips and UV 1 Thanks Bob, I'll email them and cross my fingers about the sweetlips.. Enjoy your day. PS I downloaded the picture of the clown fish off the website today, my first time downloading from the site.. Gillian <Ahh, great... a nice aquarium pic... for only 96k bytes... Many more to go... I switch my active desktop backgd. daily... and keep my light tables on... makes me (partially) believe I'm in the tropics! Bob Fenner>

UV Sterilizers I currently have a 90 gallon overflow with a 30 gallon sump approx 35-40lbs of live rock, live sand and fish. I was thinking of adding a UV sterilizer and noticed that you dislike the Rainbow Lifeguard products. If I read correctly you recommend the Vectron UV sterilizers, what size would you recommend , my current return pump flow rate is around 300gph. Can you recommend a good online store to purchase these units from ? <Don't know of anyone directly who re-sells TMC's units in the U.S.. Ask your dealer to order a suited size (for something approaching a 100% kill rate per pass) from Quality Marine in Los Angeles. Bob Fenner> Thanks, Patrick Davis Buffalo, NY

UV's Thanks you for your advice again. I had the 304 Fluval that was on the skids last week, it died Sunday. Had already set up an Eheim 2215 before it happened on a 48g pent, ended up diving the eighty miles one way to get it, hope it was worth it. <Yikes. Me too> My other dilemma is should the UV be put back inline or get a separate pump for it.  <I would put it back in-line... after the Eheim.> As far as power heads go I am using two 402's one is not working right. What is your opinion one a replacement? <Either another Hagen one of whatever size/model or an Aquarium Systems product. These are my favorite lines> I feel may need something a little bigger since the Eheim discharge is different than the Fluval. One last thing I added a Kole tang about three weeks ago and it appears my ich problem has reared it head again, I did the temp up and salinity down it appeared to go away, purchased a cleaner wrasse also. Last night had to move the LR around and this morning the Kole was covered again and the coral beauty had spots they are the only ones two get it. Today it is almost gone About 18 hrs. Could it be more stress related? <Maybe not. Would try a Cleaner Shrimp species in addition. Bob Fenner>

UV sterilizer and a start up reef tank Hi, You have such great insight and were able to help me before. My question is probably more for reassurance. I have a 55 gallon tank, with 40 lbs. of live rock and live sand. I have an Ecosystem 40 mud filter with Caulerpa in it. I have one small sailfin tang and 1 dragon goby. My tank is 3 months old and I believe is in good filtration mode. My current water values are temp. 78, Salinity 1.023, NH3 0, NO2 0, NO3 0, pH 8.3, kH 10-11, Ca 450ish. <Great> I had a huge algae bloom which then turned my water green. The maker of my filter said it was phytoplankton and suggested I use a UV sterilizer. I put the UV on and in 1 day noticed dramatic improvement. Since my trigger died, I thought it was a good time to try my ultimate goal-reef. I have been doing a lot of research and asking around. The marine stores in Missouri are limited. My questions I guess are with the UV filter, if it runs all the time, will it not kill all the algae that the inverts/herbivores may want?  <No, no worries. Will reduce the amount of water-suspended life that passes by/through the UV itself... otherwise improve water quality overall.> I did read a lot of your UV information in relation to immunity. Should I put my tank on a UV schedule, only putting it on so long, so often? <No. Better, best to leave the UV operating continuously> I have power head in the tank for water movement and my lights are florescent 110w VHO. Starter inverts: mushrooms and polyps?  <Good choices> Anything else? What other fish would you choose?  <Huge possibilities... please read through the WWM site here> Can inverts cause a 'recycling' if too many are added at once?  <Yes, but very unlikely> Otherwise what is the recommended light times? And beside Ca and Iodine supplement, what other things should be done?  <Items discussed on the WWM site> And, this may be stupid, but can you touch them or will it hurt them/you?  <Usually good to keep touching to a minimum... almost none that are harmful to humans, but you should wash/rinse your hands ahead and after being in the tank, handling specimens.> Do you use a net?  <Depends on species, usually not...> Do you just place them on the rock? Sorry. Thank you for your time and in advance for your response. <Once again, depends on what organisms you're talking about. Study, chat until you feel comfortable about specific organisms. Bob Fenner> Christine

Ich, marines, questions Mr. Fenner, I have not bothered  <Never a bother my friend> you in a while, but I have a question regarding an ICK problem. I have a TMC Vecton 8 Watt UV sterilizer, <My fave consumer line of ultraviolet sterilizers.> protein skimmer, 45 lbs of live rock and a penguin power filter on a 30 gal tank. Water parameters are for the most part perfect, and the temp never fluctuates more than one degrees from 77. I have a 65 gallon tank waiting to be set up, but you told me not to transfer the fish until the ick problem has been solved, and at this time I don't have the resources to set that tank up for a while. Well here is my question, Am debating whether to treat the actual tank. The main concern of the ick is on a yellow tang. This is my second yellow tang, I figured with the TMC unit in that the Ick problem would be greatly reduced. <A few tens of percent. Is that greatly?> Two other fish that had ick since putting in the UV sterilizer no longer show signs of the ick, but the tang for some reason, even with the UV is still getting ick. For the first week I ran the UV for 24 hours a day, but now I have switched to 8 hours of UV sterilization (How long should the UV be running?).  <Continuously... All the time. Please read: http://wetwebmedia.com/marphysf.htm> Even when the UV was running 24 hours a day , the tang still contracted ICK. I have done 2 freshwater dips on the little guy, but within 5 days of being put back in the tank, he contracts the ick. <Yes, the ich is in your tank... not just on the fish. Please read: http://wetwebmedia.com/parasittksfaqs.htm> The first time i did the freshwater dip, I put him in a separate tiny little quarantine tank for like 5 days, but once he was back in the main tank the problem returned. The problem is every time I have to get the tang out it is a 2 hour ordeal. What are your thoughts of treating the actual tank, <They are posted on our site (WetWebMedia)> i cannot remove the fish and let the tank go empty for a month or two like you recommend because of time constraints and i have no place to set up a temporary tank. I have two corrals currently in the tank, a small brain and a sunflower, but am worried because every magazine i have ever read says not to treat the main tank. <Keep reading> Majority of the ick medicines say REEF SAFE, but how reliable is that statement, do you know of any ick treatment that would not effect or damage the reef tank if directly treated.  <No, they don't exist... the "newer" ich remedies I know of are simple poisons... proteinaceous precipitants by action... they poison the fish host, making it produce more body (et. al) mucus, coating, sloughing off the external parasites... > What do you recommend, I know it sounds funny, but I really want to save the little tang, contrary to what every one is telling me to forget about him and remove him. The tang is the life of my tank. Well thanks for all your great help, and sorry that the email is so long. <No problem with the bother... do read over all the materials on marine parasitic disease including the many, too many FAQs that give glimpses of others trials/experiences.> Why is it the most colorful and enjoyable fish are the most problematic!!!! Alfredo <A corollary of someone's reductionistic "rules", no doubt. Bob Fenner> Thanks once again for your great advice and guidance.

Today's FAQs Hi Bob, Rick your reefing friend here. I read in the FAQ today that you think the Rainbow Lifeguard UV's are junk. Why do you say that. I currently own two 40 watt units and both seem to be working fine. One is 4 months old, one is one month old. I respect your opinion and if you have a good reason for not liking the RL units, I would really like to know as I will probably toss them and buy what you recommend. Thanks as always <Perhaps these units have been improved... wouldn't take much... will cut/paste my opinion sent to someone else a few minutes back re: Yikes! If you don't mind, can you tell me what you dislike about the RL UV? <Very poor design, no engineering (the water flow through-path is about the worst you could come up with)... terrible history of ballast failures (we returned all, ALL at Petcos CASCO installs over the first year of use... most within weeks...). Like too many of their products, poorly thought out... Should stop spending money on advertising and go back and make real products first. Really. Their repackaged swimming pool gear (pumps, filters) are okay... the little chotchky aquarium filters, relabeled German pumps made for constant hot water home use... a very bad joke> From the sound of your response, sounds like it might not just be useless, but harmful. Any UV preference for sterilization of pests?  <Yes... Read the site: TMC's...: http://wetwebmedia.com/UVFAQs.htm> <<Be chatting. Bob Fenner>> Rick

NYLON and UV Hello Bob, I installed a UV sterilizer and was forced to used nylon adapters from 3/4" female to 5'8 " hose. The light is emanating from the nylon (white) adapters causing them to glow. Will the nylon break down due to the UV light?? <Over a period of time, yes. I find it a good idea to replace these fittings about once a year, or approximately every two lamp replacement cycles... maybe record such on the contact chamber... And a likely-unnecessary warning... don't stare (much) at the area where the "neat purple light" is shining through (and do place such out of the view of pets, children (or tape, wrap over)... Bob Fenner> Thanks, Russ

UV use and Copper  Lorenzo, as it turns out it seems to be ich again, i did re-copper the tank using copper power, i think the queen was actually stressed from moving a sump sponge that was filled with waste, i do have Caulerpa in the tank (hopefully putting a small dent in the trates, still green as ever, the queen is still acting weird, and eating little if any. What i really would like to do is a mass water change, but there is so much water to replace. Can i run a UV sterilizer while having the tank coppered?? <Not with some types of sequestered copper. Check the label on the Copper Power re. Bob Fenner> thanks

Where to buy Vecton UV Sterilizers Hello Robert, I am ready for a UV sterilizer and I know you like the Vecton units. Are there any US distributors? <Yes. Quality Marine in Los Angeles imports these units. Their URL and that of the manufacturer (TMC, Tropic Marine Centre of the UK) can be found on the links pages of the www.WetWebMedia.com site. You may need to enlist the help of a local retailer to purchase this unit from Quality. Bob Fenner> Thanks! Steven Berg

UV light repair dear sirs am not sure if i have the right company but i have a pond clear advance uv30 that's a little over 12 months old the white connecters on each end of the tube have corroded and i wondered if it was possible to get some from anywhere i would be grateful if you could help me in this matter. <Please take a look on our site: www.WetWebMedia.com on the Links Page for the URL to Tropic Marine Centre (in the UK) and email them re this request. You may use my name in reference. Bob Fenner> many thanks Craig Hollinshead

UV Sterilizers Hi There! I have a question about UV sterilizers. Should they be run 24 hours a day?  <In most cases, yes> We use live rotifers to feed our 75 gallon reef tank and we've been told that the UV should be turned off after the main lights go off and our actinics come on, because the UV will kill the rotifers when they come out to feed on algae. Is this true?  <No... not in my experience... Rotifers are large enough to persist through exposure to this amount and kind of radiation... In comparison, probably much more of their numbers are reduced by various pumping mechanisms in your system...> Are enough rotifers living in our tank for the UV to have an impact on their population? <I doubt if this is an issue... and if I had a UV in your situation, I would leave it on continuously.> Thanks for any input, Kristin Gardiner <You're welcome. Bob Fenner>

Re: confused-urgent ick problem Dear Bob, When we put the little Naso back in his home tank, he continued to look better and the next morning his dark spots were barely there. He still looks good. We called all over town and found a few cleaner shrimps. I wanted them anyway and I hope they can avoid becoming an expensive lunch for the hermits.  <Yes, they should be able to co-exist... unless you have "mean" species of Hermits... and/or both are hungry...> I love that little Naso (not so little). He's amazingly intelligent. I hand fed him Sunday as much as he would not spit out while he was in the copper tank. Now he eats out of my hand reliably. After yesterday, though, he turns distress colors when he sees the net. I hope I can win his trust back. <You will> Thanks for all the replies. People tell us getting a UV filter will prevent this.  <No... a myth> Now I'm just hoping the shrimp and fish "bond". By the way, your web site is an excellent source of info. (I would expect nothing less given that your book was so wonderful). <Ahh, thank you> I can't help it. I love this fish. Thanks again, Allyson <Be chatting my friend. Bob Fenner> Allyson C. Rosen, Ph.D.

UV Manufacturer Ratings/Opinions  Bob,  I just recently bought an Aquanetics inline  15watt  UV sterilizer, it is rated at 480 GPH Max flow rate >and recommended 240g max size fishtank.  <Really? Fifteen watts? This isn't much radiation  for such a size system...  but at a low flow rate... of some use>  I on the other hand have a Fluval 304 rated at 260  GPH  running on my 55g fish only tank. Is this too much UV  for my system ?  <Not too much...>  and what do u think of Aquanetics ?  Thank you for your time.  <The owner, John Epps is an old acquaintance and a  good friend of our old  corporation has been there for more than a decade...  and we "live" in the  same town... but their UV products... are  inferior... very common problems  with leaking... no where near the features of better  manufacturers... like  TMC (about the best consumer units on the planet),  Emperor... many others...  My opinions. Bob Fenner>

UV sterilization and beneficial bacteria Hello Robert, I have recently been given some live rock that was left out of water for an extended period of time. So, what I am left with is some very nice pieces of porous once live rock. <Okay> I know that beneficial bacteria and algae will colonize other suitable objects when placed in an environment where they already exist on or in other objects, like live rock, but what effect does the presence of a UV sterilizer have on this process?  <As in the water in the system passing by way of UV radiation? Negligible effect> Is the beneficial bacteria and algae able to colonize the new objects or are they trapped in the existing live rock and sand, zapped once they become water born leaving the non-inhabited newly introduced pieces of once live rock fallow? As always thanks Steve B. <All a sort of percentage game... but more than enough micro-life will get around to quickly colonize/recolonize this material. No worries. Bob Fenner>

UV Sterilizer purchase Bob, I am in the market for a UV sterilizer, my question is my Fluval 304 pumps at 260gph the inline UV sterilizer is labeled at 240gph will I experience any type of problems because since it is inline the filter might over flow because the UV is not dishing out the water flow fast enough. And on your article you mentioned that it si common for a 55 gallon to use a 15watt UV but this UV am going purchase is rated at up to 75 gallons. Any suggestions will be greatly appreciated. Lost and Confused. <You're not that lost or confused... And no problems with the higher rated UV... the "overkill" here is minimal... with no real worries of... adding too much of anything other than perhaps a modicum of waste heat to your system... Bob Fenner>

Copper and UV's I have read all through WetWeb and do not see any information on this topic so here goes. I have been treating my tank for marine velvet with copper and after a number of weeks  <These treatments should go no longer than two weeks...> I believe I have saved at least part of the fish. The tank is now velvet free for two weeks. I am beginning to drop copper levels but it is proving pretty tough. The tank took almost 5 times the normal copper dose to finally get the required free level of copper in the water. <Absorbed where?> I am currently doing water changes and have a copper absorber in the Modu filter but copper levels have not budged at all according to the test kit. Copper will drop right after the water change but jumps right back after 24 hours or so. I assume it is still leaching out of the substrate etc. The copper I am using (Cuppermine)<Cupramine> said to turn off the UV during use. I did this but want to turn it back on as soon as possible. Why exactly did I need to turn it off in the first place and if I turn it back on what will happen?  <The method of chelation is defeated by UV radiation... may coat your sleeve or lamp at this point even...> Release of too much free copper, UV coated with copper, thermo nuclear explosion? This as been a long battle and I sure don't want to mess it up at this point. Help and thanks as always. <Place activated carbon and/or a pad of Polyfilter in your filter flow path and the copper will be gone. Bob Fenner>

UVs, Ozone, Stocking Questions First, I would like to say YOU’RE THE MAN. I have 180gal FOWLR tank, which includes: 150lbs. Of LR 5 inch Dragon Wrasse Turboflotor 1000 5 inch Red Sea Lunar Wrasse 30 gal sump 4 inch Blue Throat Trigger  25 watt UV 12" Snowflake Eel FB600 Sandbed 50-Micron bags used for Mechanical Filtration Mak 4 pump I was wondering after already using your dip techniques describe at the www.WetWebMedia.com site is almost useless to have a UV Sterilizer hooked up to the tank. <Has nothing to do with UV use… UV’s are useful adjuncts to improved water quality and hence health of livestock. Quarantine is a useful technique for eliminating infectious and parasitic disease, assuring the readiness of introducing new livestock, healing weak specimens…> I know that it helps improve the water quality but is it really worth the up keep.  <Depends… is the few percent improvement worth it to you?> The guys at Custom Aquatic told me that I should replace the bulb once a year and clean the sleeve every month. <Yes, good general rules of thumb. The manufacturer of the unit will give more> Changing that bulb can cost after a while at that rate. <Less than the electricity to run it 24h/d… or perhaps the money, hassle, heart break to replace your livestock> I also read your book (The Conscientious marine Aquarist) and it seems that you prefer the use of an ozonizer.  <Yes, IMO, better than a UV… but both are worthwhile> Well in reading different things at wetwebmedia I could never find anything discussing of the right size to use on various sizes of tanks. Could you help me out here? Which one of these techniques would work better for me? In addition, I can't find the DIY UV on Wetwebmedia.  <Hmm, the size of? UV’s has a bit to do with their design, effective flow rates… but a twenty, thirty watt unit will get you about all you’re going to get for this size, type system … no need to shoot for some near one hundred percent kill rate per pass… or seek to raise redox, dissolved oxygen through this means> Right now, my tank utilizes the Mak 4 pump for water circulation and I was thinking about upgrading to a Dolphin 1200gph silent series, but Am not sure, if I want to spend the money for their quietness. <Up to you.> I recently placed a small Rio pump in the tank and the fish kinda took turns swimming in its flow path (that was funny to watch). I noticed that with many different dealers in my area that they have the water inlets set-up different. Some have the inlets pointing down at an angle in the tank and others have them the top of the tank causing a ripple effect. Is there a right way into doing this?  <A little to lot of both> Am assuming if I had the inlets pointing downward into the tank that I could achieve greater circulation and a uniform temperature throughout the tank. In addition, I was thinking of adding to smaller pumps near the surface to push water toward he overflows. What do you think about adding more water flow into FOWLR tanks? Should it be just as half as much as reef tanks? <The more the better for all> My last question concerns stocking. I would like to add a 4" Gray or French angel, 6" Naso Tang, and a 4" Red Spotted Hawkfish to my tank. These would be my last additions. Would this be over crowding? <No, but these would be more than capacity with growth… Okay for a year or so. Bob Fenner>

UV lights and nitrates Hi, I have 90g saltwater with live sand and live rocks, I thinking of buying UV lights but not sure what brand, size watts and gph to run it. I also having problem reducing nitrates in my tank over 60ppm I lost some of my fish already please help me!!!!!( I change my water 25% every week using reverse osmosis not tap water but seems like I can't bring it down no matter what I do.( I should put more live rocks in). (no nitrites or ammonia, ph 8.2) Thank you for your time Randy <Hmm, do re-read your message here... needs proofing... Read over the site mentioned below for articles and FAQ's on lowering nitrates.  An ultraviolet sterilizer for this size system? Hmm kind of depends on rate of flow of water you want to push through it... but a twenty or thirty or so watt unit's about right. My favorite make/model? Do read over the UV piece on the site: www.wetwebmedia.com and the review of the company, Tropical Marine Centre, and look for one of their units (or ask your dealer to order one for you)... Bob Fenner>

UV's, Parties, and Upcoming Fish-FUN  Hello Bob!!  My name is Shaun von Hecht, we met at the Sacramento  Marine Aquarist convention (You spoke on Echinoderms,  remember the after party??). <Oh yes, good times>  Anyways, I'm very happy with your views &  recommendations, so I thought I might ask you a couple  questions, if you don't mind: <Fire away>  1) one of my service accounts runs 2 U.V.s : a 15  watt Aquanetics & a 25 watt Life Guard, in series, the  25 watt is first. The tank is ~200 gallon marine "fish  only" triggers, grouper, wrasse... tuff stuff. So, my question is, is the 15watt unit still  effective due to the larger unit being first? How effective are multiple U.V.s in series, compared with  1 "big" unit? Flow rate is no more than 150 GPH. <I suspect you and I are in agreement here... Watts are Watts and exposure time, proximity to the ionizing radiation are all that are important...>  Also, I know this isn't the best configuration out  there, but as a servicer, I had to make due with what  was available to me. <I understand, and agree... have been there/here many times>  2) what brand carbons are you partial to?? <Eheim, TMC's high-retention (HR) brand, for cheapy "in town", the Aquarium Pharmaceuticals highest (of three) qualities...>  I usually use Marineland & Rainbow Lifeguard pellets. <These are okay, passable>  Thanks for your time!!  Shaun <Anytime. See you at the next WMC, Monterey. Bob Fenner>

Help, UV Sterilizer hook up Mr. Fenner- A friend gave me his Aquanetics 8 watt hang-on UV Sterilizer, that was only a few months old. My question is how to hook up this unit. He gave me the unit and two 1/2" tubes. I purchased a Penguin 550 Powerhead to run it. Where do I attach the tubes? Sorry to ask a dumb question, either I am confused or I do not have all the parts I need. I would appreciate your help. Thanks again! Cory >> <Tubes? The barbed connectors are best attached between the discharge of a pre-filtered pumped water source and back to the tank or sump... use at least one non-metal clamp device on the tubing over the barbed fittings... Take a look at the diagrams in the article on UV use stored: Home Page  Bob Fenner

To UV or not to UV? Hi Bob, Thanks so much for getting back to me. I actually did that while waiting your reply. The water is now green!!! ARRR!!!! Why is this happening? I have  also limited my lighting time to 3-4 hours a day. Would using a UV Sterilizer help? Thanks so much again.Brian  >> System is "out of balance"... more light and somethings to use it would help more than a UV... live rock, macroalgae... in a sump, or the main system. Bob Fenner

UV Flow rates included with my UV light was a chart that illustrated flow rates-vs..-kill rate. I have a 3ft.in length, 3inch diameter, 30 watt light. > What flow rate would you recommend? I'm using it in a 75gal. reef tank where it is attached to my sump return via a "T" valve so as to adjust rate or by-pass at will. <Hmm, in the present configuration, there is a point of diminishing returns... where the increased flow, though of lower "kill per pass" ratio is not "worth it" in terms of alternately passing the water to your main system (instead... for the benefits of flow, aeration...) I would move no more than 150 gph through the unit... and no less than half that... in actual flow. To determine this (don't trust pump ratings...) get a cleaned up "fish bucket" of known volume and a watch with a second "hand"... and time how long it takes to "fill the bucket" up to a determined volume... do the math... how many gallons per minute/hour... Bob Fenner>

UV, other gear choices well here we go again. want to spend more money. ozone or UV sterilizer. LFS says i will need pump, dryer, and carbon filtration for ozone. <Depends on where you place the ozonizer... a pump is unnecessary if you can rig up the discharge on the intake of a "venturi" intake in your system... like the air intake for your skimmer... And a dryer/desiccator? Not essential even in relatively moist environments... unless you prize the greater efficiency from drying the air before it goes into the ozonizer... even then you can make one inexpensively...> although i can get several options (ORP, etc), it seems considerably more expensive than a UV sterilizer.  <Well, one of the chief benefits of working Ultraviolet Sterilizers is their production of... ozone... but the ozonizer does produce more...> is it that much more efficient? we are also in the process of adding a sump with Berlin skimmer with Rio 2100 and Rio 2500 for return. you know it is a shame that LFS don't spend more time with us newbies. if i had gotten all of this new stuff on the front end, i wouldn't be stuck with a canister filter, undersized skimmer, undersized exterior filter and god knows what else. well what do you think, UV or ozone? thanks Jim nix  <For your system, a UV... for now. Bob Fenner>

UV sterilizer... too much? Hello again. Does a UV sterilizer get rid of anything from the water that the fish need? Is it good to let it run all of the time? <Nothing that's ultra-important... do leave it running continuously>  Also, I have hung my UV sterilizer on my wet-dry filter instead of on the tank itself. Will this kill something that the wet-dry needs in it? <No, but it might be more useful to place it returning to the main tank... to reduce the incidence of bubbles going through it (cuts the efficiency), and will give you the most kill per total passes, improved water quality...> Thanks for your help. Chris A. Johnson <You're welcome. Bob Fenner>

UV Sterilizer, help with Crypt... some Hello, I have another dreaded ick question. I am considering purchasing a UV Sterilizer for my FOWLR tank. It is 120 gallons with wet/dry, and a protein skimmer. I was interested in knowing in your opinion do the sterilizer really help eliminate the ick infestation. Is there any particular brand that you can recommend? Lastly, if there are no visible signs (i.e., white spots) on the fish does it necessarily mean that the fish is not infected? I know it's possible for the parasite to be in the gills. But, wouldn't there be a sign of heavy breathing? Thanks once again for your enlightened help. Tanya >> An ultraviolet sterilizer does/will help to control ich (and other water-borne) diseases... through improved water quality as well as "zapping" parasites... But it will not generally cure an existing problem, nor totally disallow their possibility. Careful selection, handling, acclimation, dips/baths and quarantine are just as important in avoiding and curing these problems. The UV units made by Tropic Marine Centre are superlative... There are residual infestations of ich that can/do come from "resting stages"... Though most of these do not "originate" on their ultimate host fish(es). Put another (hopefully clearer) way, there are specific pathogen-free fish livestock collections, where ich has been excluded from a system where marine ich won't just "pop up"... unlike freshwater "ich" of the same name, different holociliate protozoan cause. Bob Fenner

UV set-up Hi Bob: I need your advice again. I am planning on hooking up a Magnum 350 to my 110 gallon reef tank. I have about 70lbs of live rock and a large trickle filter (sump) under the tank. I also have a protein skimmer which doesn't seem to do much. My water always seems to have small particles flying around and is never crystal clear.  Question 1: would you recommend using the Magnum just with the micron filter or should I add carbon and phosphate remover to the filter? I know my phosphate levels are too high, and the water seems slightly tinged with yellow when I look in from the side of the tank.  Question 2: I've heard you can attach a UV sterilizer to the magnum, but how do I configure that? Which UV would you recommend for my size tank? Thanks, Jill >> I would hook the Magnum up with the filtrant module (not the micron) with the Dacron sleeves (for mechanical filtration) the company sells surrounding it, and place a bag of either Chemi-pure (my first choice) in it (or the equivalent activated product from Aquarium Pharmaceuticals...), and maybe switch this filtrant out every month. This will also remedy the color of your water... Skip the phosphate remover for now... An in-line UV (Ultraviolet Sterilizer) can be fitted to the discharge side of your Magnum's tubing, between the filter and the black fittings that convey the water back into your system. A drawing of these sorts of arrangements can be found in an article on Physical Filtration I have stored at the URL: www.wetwebmedia.com for your perusal. For the size of your system, flow rate of the Magnum I would invest in a 20 watt unit... My choice of manufacturer? Tropic Marine Centre. Bob Fenner

UV sterilizer sizing I was just wondering about your opinion on UV sterilizers. I have a 75 gallon tank, mostly fish but a few corals. What size would I need and do I run it all day, 7 days a week? I didn't know if this would take out all the nutrients for the corals. Do the sterilizers really help with disease prevention? I lost a cow fish and brown tang just yesterday from what initially appeared to be ick. It seems that only a small few of my new purchases survive, but my established fish seem to do well. Thank you for any help in this matter. >> Hmm, yes, Ultraviolet Sterilizers are useful adjuncts (additions) to otherwise well set-up, filtered and maintained systems... They do enhance water quality, increase dissolved oxygen concentrations, lower the incidence and virulence of water-borne infectious and parasitic diseases... Now, as to size, this really should be matched with the flow rate of whatever pump source you're going to use... Makes sense to not "overpower" the given rate of flow that you can zap to near a 100% kill per pass... so match the flow rate with the dwell time... All real manufacturers will give a standard linked to gallons per hour... flow rate. And, nah to the UV extracting nutrients from the water... negligible effect. But, hmm to your persistent losses problem... might want to review your selection practices... dipping/quarantining/hardening routine... and possibly consider some biological cleaners... You either have poor fish from the get go (try another dealer), an anomalous condition in your tank (like overdosing history from supplements, or a toxic blend of salts from something like removing the crust from your top...) or a biological condition that your extant fishes have adapted to, but is too much for new ones... Bob Fenner

Lighting and U.V I have (one year) a 100gallons marine aquarium, 22" Height, 5 fishes, 3 soft corals, 1 small Tridacna, 5 hermit crabs and 1 red starfish. Lighting: 3 36w Power-Glo and 2 36w actinic. Kalkwasser is added 3 or 4 times a week ( total:1 gallon) 10 gallons sump top-off DI water In the present some slime algae are giving me some trouble and work because I must brush them off and clean the mechanical filter often. Recently (10 days ago ), one U.V sterilizer is in place in an attempt to minimize the algae problem and at the same time, to face a 12 days ago ich problem. So, I would like if you could give me your important opinion about the following: - the lighting.  - If I add, in the sump, some Caulerpa, what kind of light must I use there? Full spectrum fluorescent lamps? - When must I disconnect the U.V unit? Today the water is very transparent, the fishes are great and the corals are looking very healthy.  >> Your lightings okay (but could be brighter...) but do check the age of your lamps... they're really only good for 8-10 months at 10-12 hours per day... and should be cycled out one a month...or so. Do add the Caulerpa... and another or larger sump if it will fit... and yes, the full-spectrum fluorescent lighting as well... Maybe you can get a Compact Fluorescent for the main tank and move a couple of the current fluorescents down below? You never have to disconnect the UV and I wouldn't ever... it's made for constant use...  Bob Fenner

Coralife Mega-watt UV Sterilizer Hi Bob, First off, I have your book and I have to say it is very well written and informative. I enjoy it tremendously. Anyway, I am doing an initial investigation on UV sterilizers. A few days ago, I came across a website which was endorsing the Coralife Mega-watt UV sterilizer for it's efficiency, ease of maintenance, and relative low cost. I am wondering whether you have any experience with this particular brand and if so, could you tell me more about it? This will be my first UV sterilizer. Can you make other recommendations, taking into consideration the cost and the ease of installation and maintenance? By the way, I have a 75-gallon FOWLR tank. Thanks. Boon >> Thank you for writing... and yes, I do know the unit (have been to the folks, place that make it for ESU/Coralife)... and rank it about in the middle for "design, construction, utility, overall value"... It's not as bad as some of the other major brands in terms of leakage... or junk ballasting... But I don't own/use this model/brand... My more complete ideas on ultraviolet sterilizers, including a parts list on how to assemble them DIY, and installation are archived in an article at www.wetwebmedia.com and my opinion re the better, best features and the companies that offer them have not changed... for many years. The number one make/models are produced by TMC (Tropical Marine Centre)... and are thankfully distributed in the US (your dealer will know by whom)... For inexpensive, hobbyist-intended applications the TMC/Vecton line is made "for the job"... not just PVC pieces and compression couplings and spare electrical fittings cut/solvented/clipped and pushed together... They come with sleeving... remoteable ballasts, rigged for hanging, and are engineered for maximum kill rate per rated pass... they do the job, last the longest, are a relative joy to work on... In a word, provide VALUE for the money.  Wow, guess this is clear! Thank you for writing. Bob Fenner

Re: UV or not UV? That's a reef question Thanks for your reply. The reason I asked is that in the book you suggested that a UV unit might result in an immune problem and kill good necessary microbes as well as the bad ones. My wife bought me a UV unit for Christmas, and I'm am trying to figure out if I should use it on my 50 gal reef. If so, should I run it less than 7/24? Does using this unit reduce the risks associated with using free Scripps (SIO) water. Thanks again. >> I would use a UV if I had one on any given reef system... And yes to reducing the chance of introducing undesirable microbes from the raw (but sand filtered and free) water from Scripps Pier... I would still store it in the dark, circulated for a week or so before use. Bob Fenner

In a nutshell, are UVs beneficial or not, or not much?  I have read so many opinions one way and the other - can you comment? Thank you for your answers - your column is a wonderful resource. Urey Patrick >> UV's are beneficial,,, for killing much of the in-water microbe population, raising dissolved oxygen and reduction oxidation potential >> Oh, and stop touching those buttons too soon: Let's see, where was I? Oh yeah. UV's are of use, but how much? A few to several percent improvement in disease prevention and water quality improvement. Is this "worth it"? IMO, only after other aspects of water quality have been looked after. Biological filtration, mechanical, skimming, even ozonation and a dryer are more important... Bob Fenner Preventing Parasites with a UV? Nope Hi Bob ! I have a 55 gallon reef/fish setup. In order to help prevent parasite outbreaks I would like to hook up a UV sterilizer IM a little confused on the size to get and do you recommend one? Thank you.  Richard Tarr >> Hmmm, well let's see. First off, I would like to (so I will) state that such a contrivance will not prevent parasite outbreaks... but it will help to do so. I would definitely run your new livestock through dip/bath and quarantine procedures in addition... and this should do about as much as you can prophylactically... Now, the "size" of UV is a function not only of your size system, but also of the mechanism used to run water through the "contact chamber" for an effective "kill ratio" per pass... you understand? But about 20-25watts is what you're looking for... place the UV in line with part/all of your circulation/filtration gear as the last item before the water is returned to the main/display tank. Bob Fenner

UV FOR Reefs Bob, I have a 120 gal reef system. live rock/sand/skimmers. Will UV kill the nitrifying bacteria, etc that a natural system needs to continue the ecosystem?? Do you recommend the UV? Wayne >> Hey Wayne, thanks for writing. No, the UV won't kill off your nitrifying bacteria. Most of these are situated/attached to hard substrates, and the UV's only zap what passes by them in the water column. Yes, I do recommend UV's, they do a great deal of good besides reducing overall free-living microbial populations: higher dissolved oxygen, reduction oxidation potential.... Better water quality over all. But they are not the most important piece of reef-keeping gear for hobbyists IMO. Way before you should have good filtration and circulation... Bob Fenner

Great Book! UV, Crypt Bob: I had to get out of the marine aquaria hobby about ten years ago, and have been itching to get back into it ever since. I picked up a copy of your "Conscientious Marine Aquarist" earlier in the year, and have thoroughly enjoyed it. I have found it to be extremely comprehensive on subject matter. Of course, the color pictures are fabulous, and I especially enjoyed the chapters on various species in the second half of the book. It was the catalyst I needed to get back into the hobby! I've also found it to debunk some bad advice I've been given at a few aquarium shops. I set up a 75 gallon tank back in about June, and currently have ten fish. However, I seem to have a persistent ich problem that cropped up a couple of months ago. I have a 10 gallon quarantine tank, and of course, could not remove all my fish to that tank for treatment. Consequently, I had to add copper to my main tank. I added Coppersafe, and maintained the level between 2.0 and 2.5 ppm for about six weeks. The problem seemed to subside, and afterward, with water changes and activated carbon the level dropped to 1.5, and then symptoms reappeared. I added more Coppersafe, but lost a Double-Saddle Butterfly before the added medication started to take effect. Am I forced to permanently run copper in my system, since I can't remove all my fish to my small quarantine tank while I "sterilize" my main tank. I've been told that ionic copper is more effective than chelated (Coppersafe). However, the instructions on the ionic copper state that it should not be used with any chelated copper in the system. Anyhow, I'd never be able to tell how much ionic copper is in the system as long as there's some chelated copper in it. Any suggestions? I suspect you're probably very busy, so if you can't respond, I understand. I mainly wanted to tell you how much I've enjoyed your book! >> Thank you for writing, welcome back to the fold (the marine hobby), and I always have time for (high praise and) offering my help.  I hear you on the dangers of constant copper use... and the mixing of chelated and non-chelated forms.... Don't do it! Or at least (for browsers, but not in your case), remove the "old" copper first with activated carbon... Now, what I would do in your case: Unless you have a big, mean fish like a trigger that will munch them down in a sec., get a couple (two) of the following: Lysmata Shrimp (amboinensis) and Gobiosoma gobies... Not to worry if these species don't occur in even the same ocean as your other livestock. With low grade, consistent infestations as yours, these facultative cleaners are just the thing to tip the balance in your fishes (and your) favor. Bob Fenner

I am considering purchasing a UV sterilizer to kill the parasites on my fish and then prevent them from coming back again in my new 75 gallon aquarium. I have heard that having the correct flow rate is necessary. What flow rate would you recommend. The UV I am considering to buy has a 25 watt bulb and a 3inch diameter and is 17inches long. >> Don't mis-invest your time and money. A ultraviolet sterilizer will not, repeat NOT kill parasites on your fishes... it will kill some water-borne micro-organisms and aid in producing higher quality water conditions... but you should first put your money and efforts into preventing the introduction of parasites, infectious disease agents and weak new livestock, by purchasing, setting up and operating a quarantine/hospital tank for all new livestock... take a look at the articles on disease, quarantine on the wetwebmedia.com site... Yes, UV's can be worthwhile, yes dwell time is important, yes, some brands are much better than others (I like the Tropical Marine Centre line best, for reasons I list in articles at the site listed)... Read on. Bob Fenner