what are the pros and cons of a uv sterilizer

[j_man]

what are the pros and cons of a uv sterilizer? does it kill ick, velvet or anything else? Does it interfere with nitrating bacteria?

[BubbaWPB]

Pros: if it is set up right*, it kills circulating microorganisms: bacteria, phytoplankton, and circulating parasites. This helps to keep these sorts of organisms under control. It is considered a good adjunctive treatment for ich (in addition to some of the less-effective but reef-safe treatments) but does not treat ich on its own. It works to sterilize water if the water gets a single pass through UV (at adequately slow speed and adequate UV intensity) prior to adding the water to the tank - it is often used to sterilize natural sea water

Cons: Circulating tank water through the sterilizer usually cannot totally irradicate any circulating organisms. It does not irradicate ich from the tank since one of the life stages lives in the sand, and another stage lives on the fish, but it can help cut down on the circulating ich stages. You must keep the crystal clean so that the UV light can penetrate the circulating water. (The clearer your water is, the better it works.)

I think my water is clearer and have had much less algae problems since adding a UV sterilizer.

* set up right = flow is not too fast through the sterilizer and the light intensity is adequate in intensity for the water flowing though

I'm sure if you do a web search on UV sterilizers in aquariums, you'll find more than you wanted to ever know on the subject.

[BubbaWPB]

OH... it does not interfere with nitifying bacteria since they usually live on surfaces in the tank and do not circulate in large numbers.

[Poseidon]

^ what he said!

I am considering one for my tank. Not to dissagree with Bubba, however I think the UV will actually HELP in clearing the water, by destroying free floating algae spores. My eventual plans for this tank include, UV, Ozone, Kalk, and Ca Reactors. This is probably the order of addition too!

[golfish]

Pros: if it is set up right*, it kills circulating microorganisms: bacteria, phytoplankton, and circulating parasites. This helps to keep these sorts of organisms under control.

Some people might argue that this is a negative thing when used on a reef tank.

[BubbaWPB]

Not to dissagree with Bubba, however I think the UV will actually HELP in clearing the water, by destroying free floating algae spores. My eventual plans for this tank include, UV, Ozone, Kalk, and Ca Reactors. This is probably the order of addition too!

No disagreement at all! Mine has helped clear my water... it's just the light needs to penetrate the water for it to work. The UV is less effective the more turbid the water is. Destroying algae spores is a REAL good thing when you're trying to clear your tank of bubble algae.

P.S. I pick up my ozone reactor tomorrow and have already done the calcium reactor (the best investment I've made for my tank!)

Some people might argue that this is a negative thing when used on a reef tank.

Well, the whole purpose is to sterilize the water.... the argument is theoretical, and the proof is in the pudding. I've never read of any reports of problems being caused by adding a UV sterilizer to a reef tank. If it had a negative effect on bacteria, you'd expect a spike in nitrates.... ...and who wants more green algae settling on the windows, rocks and inhabitants?

[showfish]

As, with many things in this hobby this is one of those topics that can be debated on both sides. I’m on the side of the fence of the believers. I run one on my 120 FOWLR and truly believe it helps in clarifying the water. Whether or not it helps control ick however, is another debate. I think it can certainly help especially when the parasite is in the free-swimming stage, but is definitely not a cure-all for ick control. The main thing here is water flow. Proper exposure of the water thru the UV is the key to its effectiveness. I always make sure to clean the glass sleeve that surrounds the bulb once every couple of months.

[scubadude]

My thoughts are that a UV is an ultimate addon but only should be used with control such as switch inline with the pump and/or light and maybe a ball valve, So you can control the times you turn on/off.

[Gmoney!]

I have been researching this, but have no personal experience with UV in my tank yet, but I have been doing this for 10 years...from what I read, you must buy a UV that can do the following:

A)Slow enough flow to kill parasites/bact
B)Fast enough flow to turn your tank over 4-5 times its size.

In other words, if you get a UV that needs a flow of 150gph to kill parasites, but your tank is 200 gal, sure you will be killing parasites, but you will not be turning enough water though it to treat the entire tank. On the other hand, if you increase your flow to treat the entire tank, it wont be slow enough to kill the parasites.

Thus, many recommend if you are going to go with a UV, you should get an HO unit...Emperor Aquatics seems to make the best HO units, and a 50w UV can kill parasites at 500-700gph, so it should be able to handle tanks in the 120-150 range...it isnt cheap though... $480 was what I was able to get it down to...

I think a UV is a premium item for a reef tank, meaning you can run a reef tank without one...but if you have the cash, definitely get one, and get the right kind... dont waste time with these cheap 10-25w UVs... they are useless and they are the reason many dont believe UV work... get yourself a 50w HO from emperor with a 5in diameter body, and then I think you will see a difference.

G

[BubbaWPB]

I think a UV is a premium item for a reef tank, meaning you can run a reef tank without one...

Agreed. Many people I know with reef tanks are successful without them. It is a nice option, as you say.

[charlesr1958]

A bit lengthy, but .....here is my take on UV Units.

Chuck