Ultraviolet Sterilizer?

For algae they work great - definitely a great solution to reduce.

 

I think they are good for algae in the water column, but that's more or less their limit. Personally, I think bacteria and plankton are your reefs friend though and should be encouraged. UV will tend to kill this stuff off instead, so even if more work, I prefer other methods to keep my glass clean. Some people like to keep their reef fairly sterile with fish and corals, others prefer more diverse fauna. There can certainly be benefits either way. In the end though, it's sort of a personally preference.

My only big issue with them though is claims that they will prevent disease, there is plenty of research on this from the aquaculture industry. The only way they have been shown to effectively prevent disease is in multitank systems, with shared water. You can prevent transfer of pathogens from one tank to another, if large enough and the flow rate slow enough.

Certainly some reefs do well with them, they will not make the tank completely sterile, as infauna will not pass through them. They can limit food sources though to an extent though and since food sources are already significantly less available in our tanks than a reef, I tend to think this isn't the best thing. After all corals didn't evolve into walls of mouths for no reason, but that dosn't mean they can't survive and grow with limited food supply. They certainly don't tend to grow at the rate of corals in the ocean though, and food is likely a major reason why. So, I prefer to encourage it as much as possible, but that's just my .02.

 

Corals don't care whether the bacterioplankton nor zooplankton is dead or alive. Filter feeders don't care whether phytoplankton is dead or alive. {Most} fish don't care either. In other words, UV sterilizers don't beam these things up out of a tank like Star Trek. They are still in the tank, just dead or wounded. The Carbon, phosphorus, and other elements are still in the tank and will be eaten.

 

It sure is nice never having film algae on the glass Mine is a small In Sump model so my exposure time is probably less than most but my H2O is crystal clear and so is my glass.
For a hundred bucks its worth it.

 

i looked at this before just for the heck of it and it looked like junk i bought a jbj last month and was really unpleased with it also there both similar

 

To an extent this is true. However, there are some exceptions. Here are a few, but certainly not all.

First, likely it will give benthic species a competitive advantage for resources, which would be expected to shift the balance away from pelagic fauna to an over abundance of benthic species. This will most likely limit diversity.

Second, protein skimmers already remove a lot of pelagic fauna, but can only skim out surfactants which limits the skimmable fauna. Not all fauna is sufficiently amphiphilic to be skimmed efficiently. Once you kill it with uv, then they will start to break down and this will absolutely make them more amphiphilic. So, they are much more likely to be removed via the skimmer before they are consumed by corals.

The third thing to keep in mind is uv is a mutagen and may lead to fauna with unpredictable mutations. I'm not saying you are going to get bacteria with superpowers or anything, in fact I can guarantee this won't happen However, this could just be sterile dysfunctional fauna, or even possibly uv resistant fauna. Back as an undergrad, I spent 3 years working as an RA in a molecular biology lab. A common way to get new mutations to study was to bombard a larva or bacteria with UV and see what survived. Often they would have interesting traits and characteristics. It's impossible to predict what the result would be in a reef, but almost certainly some organisms will survive with new properties. If your goal is to eliminate cyano, I don't think you want uv resistant cyano... it is a possibility.

 

The new marine fish and reef annual mag has a article on it it has a clownfish on the cover

 

What you just said sounds identical to what a speaker said at fall fest 2010 in iowa. He said pretty much all the same stuff. interesting.

 

The idea sounds great and all so I went and bought one awhile back myself but I didn't see much of a difference so when my bulb burnt out I took it out and my tanks been the same without it.

 

I have an in sump UV from an old FW tank. I have never used it full time. I keep it in case I have a major ich outbreak or my water was getting green. The only time I have used it in my SW tank was shortley after setting it up when I had an algae bloom and water turned green. I ran it for a week, water cleared up and I took the UV out.