UV Sterilizers?

[FishHobby99]

My goldfish tank has minor algae growth. This problem may be due to replacing the HOB filter with a sponge. The HOB is back & the sponge is still in use, providing aeration. Another problem maybe too much natural & LED light. I was hoping to encourage plant growth. I can work on that. Params good.

I am looking at UV Sterilization online. Overwhelming! Seeking guidance here before getting lost in the Amazon.

 

[Colin_T]

Don't waste your time or money on a UV steriliser, especially if it's only for algae.

Algae grows anywhere there is water and light. If there are no live plants in the water, then algae will grow instead.

The easiest way to control algae is to either reduce light and nutrients, or increase the number of live plants so they use the light and nutrients.

If the aquarium is near a window, put a picture on the back of the tank to reduce the light coming in.

Reduce the lighting time by an hour a day and see how the algae grows over the next 2 weeks. If it's still a problem, reduce the lighting times by another hour. Monitor for 2 weeks and continue reducing the lighting time by an hour until the algae stop growing rapidly.

A small amount of algae is good, it's only a problem if the tank turns green in a few days.

 

[Byron]

I’m not buying one now. Yes, it would have been for algae only, but are they of any use in controlling pathogens as well, like their manufacturers say?

Not really. In an aquarium, the water passes through the UV and then back into the tank mixing with the rest of the water. Unless all of the water can somehow be run through the UV and not return to the tank, until all of the water has been treated, pathogens will easily slip through. They are of very little value (more likely none) for algae, except in the case of green water. But even here the water is still mixing.

 

[xxBarneyxx]

Yeah I have uv filters but only use them if there is something they will help with, like ich or I have livestock that is prone to waterborne parasites (this is really only marine).

In both cases it is a supplement and wouldn't solve the problem by itself.

 

[Byron]

Thanks. Good to know. I keep seeing these words: green water. What’s that? Water heavily overran by green algae? I have nothing like that. Saw some ghastly pics online. Water looked like the pond out front. Never used. Full of some nice plants that die off winters & make a mess

Green water is caused by a rapid increase of unicellular algae. This lives in water, not on surfaces like most of our algae. It is usually a sign of very high organics and obviously requires light. Let's hope you never encounter it; I never have.

 

[Colin_T]

Don't bleach them, don't do anything except reduce the light and do more water changes, or add more live plants. It's that simple. Either add more plants or reduce the light and nutrients.

 

[FishHobby99]

EXACTLY what I’m doing right now!

 

[PheonixKingZ]

UV sterilizers are only useful if you have a sump, for the reason that @Byron mentioned.


Manual removal, light decrease, and nutrients check will reduce algae.

 

[Colin_T]

Some marine fish can be difficult to keep. Avoid butterflyfish, big species of angelfish (marine ones), pygmy angelfish are pretty good and not as much of an issue. Most Anthias are hard to keep so avoid them.

The following marine fishes are pretty easy to keep.
Anemonefish, damsel fish, wrasses, leather jackets/ trigger fish, blennies, and gobies

 

[Arthur11]

I am facing cloudy water and algae blooms in my tank. But luckily, Fluval in Line UVC Clariifier solved my problem. I was astounded because the water in the tank had become crystal clear after only one day of use, and the algae that had been giving me headaches had been cleaned up.

 

[StevenF]

UV sterilizers only work on microscopic organisms floating int the water. Any algae or bacteria floating in the water will be killed once it goes through the UV sterilizer. Any algae stuck to glass, substrate, or plants will not be killed.

If can be affective against parasites and bacteria if it treats the water faster than the organism can reproduce. Ideally you want a sterilizer that will treat all the water in the tank in as short of time as possible. So if you have 20 gallon tank you want to know how many gallons per hour will flow through the sterilizer in an hour. And you want to know how long the water is exposed to UV before it exits the filter and what percentage of pstogens are killed when the water leave the sterilizer..

Sadly most if this information is not listed on UV sterilizer packages. And I suspect for many of them the water flow through the filter is very slow or the UV light is not strong enough to kill all the potogens in the water before is leaves the sterilizer.