I battled Coolia for over 2 years. Luckily my tank sprung a leak so I bleached my rock. If it's not going into the water column at night you aren't going to beat it. I tried everything! If it is going into the water column your only hope is to plumb your UV in a closed loop on the display. A tiny UV like that needs about 150gph flow which is a trickle. You didn't say what size your tank was but if it's over 50, your UV is probably not going to cut it. You can't process enough water in time. I ran a 57 watt at 300gph on a 130.Bumping this thread as I’m almost certain I have Coolia too. What kind of pump was used in the DT? Regular return pumps? I’m going to replumb so I draw water from my DT but keep my my UV in my sump and just have the return of the UV stay at the return chamber (theoretically the same as dumping it back in my DT). I’m using a dc return pump rated for 500gph for my 25w UV, but it’s a regular return style pump with a not so fine grate at the intake. I guess I can put a sock on the end of the other side of the UV to make sure detritus dowsnr get in my return chamber.
There’s one corner of my tank that detritus accumulates slightly, so I’m guessing that’s the best place to pull water from as the Dinos should end up there the most in terms of where the water column goes?
if you want to throw everything at it and give it a shot, follow my UV advice, dose silicates at 2ppm, raise your nutrients and start culturing pods and phyto. You will go broke buying enough to handle the job at hand.