Aqua UV Flow Rates/Dosage

[tymo92]

I was planning to get a 40W Aqua Ultraviolet UV sterilizer for my upcoming 240G mainly for the purposes of helping manage fish disease.

Aqua UV's sizing charts however are far off from other manufacturers on the dosage required for controlling disease, especially ich. They say 90,000 uw/cm is good, Pentair says 180k, and other posts and literature here say even higher.

If I ran this 40W unit at the recommended 967gph to get a 90k uw/cm dose, is that too low for fish parasites? If I ran it slower though to get a higher dose, I'm worried about reducing tank turnover too much to be effective.

 

[KrisReef]

The impact on parasites is effective to reduce the living population of them and reduce the stress on the fish and gives the fish a chance to survive and fend off the disease and develop their immune systems. The uv is not going to eliminate the complete Ich population in the system.

Having a good return flow from your pump can be maintained by dividing the return flow so that you have a good kill rate through the uv and a second untreated flow from the sump to supply water circulation.