apr123

I had the same problem. I have since started keeping a quarantine tank but the main tank still has some crypt. I did get a UV sterilizer (24 watt) for my main tank (26G; so 24watt is probably overkill). It helped tremendously. I think the key is to run it minimally. I now look for spots on the fish and scratching behavior and as soon as I see any of this run the UV for a day or two. You may not be able to kill all the parasites in their free swimming state but if you can get rid of most of them, the fish (if healthy enough) can handle the rest. Every time I have done this, the fish have returned to good health within a day or so. Hopefully, at some point all the crypt will be gone. I highly recommend the sterilizer but only run when needed.