If you can force them to go into the colum then the uv will help.I had uv on , but wasn’t doing much. Its not the dyos that disappear when lights are off, and then go to the watercolum.
Draw and return into the tank. Suck out what you can and Do a lights out to help force. H2o2 at night like you are doing and microbacter 7 every morning.
Find out which ones you have of you can.
