A week ago I added a CO2 injection system to my 60 gallon planted tank (about 1 bubble per second under mid to high light). After five days I noticed that the water had turned green. At the LFS yesterday I picked up a U.V. Sterilizer which I understand should be able to get the green water under control.
What I'm wondering is if there is anything I need to be aware of or watch for with the U.V. Sterilizer. For example, is it going to kill "good" things as well as "bad?" How can I keep an eye out for problems?
You shouldn't worry. UV sterilizers only eradicate pathogens and algae that pass through it and by the UV light. All your beneficial bacteria that have colonized in your filter and in your tank will be unharmed, since they are sedentary.
Another question. Do most people with planted tanks end up using a U.V. sterilizer at some point? Or am I doing something wrong? Also, will I want to run it all the time or just until things clear up?
I had issues w/ green water in my 90g and used a UV sterilizer (9W turbo twist) which cleared it up very quickly.
Later I removed it and the tank was green water-free for many months.
Recently after doing a big re-scape and disturbing the substrate a huge amount green water began to develop again. I have since re-attached the UV sterilizer (in-line) and have decided to run it continually.
I do not believe it kills any other algae than free-floating but it is also supposed to kill free-floating parasite--if you have the flow rate set such that the residence time of the water in the sterilizer is sufficient.
From reading threads here I believe many people run these continually without issue.
Dont UV filters need slow flow rate for better efficiency, having it inline I suppose that would have a very high flow rate. So wouldnt the effieciency drop?
The flow rate will dictate what things it can kill. You need a slow flow rate to kill parasite but to kill green water you can have a pretty high flow rate.
Each UV sterilizer model specifies the flow rates needed to kill different things in the water. Larger units can handle higher flows.
I have mine plumbed into my Magnum 350. When I am using the micron filter cartridge the flow rate drops off as the cartidge gets plugged--and the UV light becomes more efficient.