Wow this post is getting big quick... I just read it for the first time... Sorry I missed it.
Zac like the others are saying chem clean is a bandaid.. And with your corals doing poor adding chemicals IMO
is not the way to go.
Light- Cyno needs light but shutting off your tank lights for 24-36 hours will not make it go away for long. I had it BAD in my fuge and I had to shut the lights off for over 2 weeks to make it go away. So IMO
the light is not the main problem.
cyno needs a food source, you need to find it and then cut it off..
in the water is food for cyno, if your showing lets say 1 then there is more them 1 in the tank, remember cyno is feeding off this stuff so it is using it to live so there is more like a reading of 2 in the tank. You need to test top off water for PO4
, that is how it was getting into my tank, top off for my kold sterile unit the PO4
level in my well went up this summer.
Wash corals in tank water you have in a bucket and use some hose and syphon it off them. Corals are tough so do not worry about hurting most of them.
Phosban reactor is IMO
the way to go.. $35 at marinedepot now..
I got mine and within a month the cyno was reduced, I was also doing water changes with ro
water and syphoning the cyno off the SB also.
The PBR comes with enough phosban to treat 150 gallon tank and it lasts for 3 months depending on how bad the PO4
Power head take it apart and soak it in vinager for a day to clean it well.
So to wrap it up.... any level of po4
is BAD.. chemicals are a quick temp fix, Low flow and wrong spectrum lighting also help cyno grow..
Nitrates can effect the health of your corals....
Good luck and keep up the fight... it took me a year to break down and get the reactor, I wish I did it earlier when I look back at all the water changes and extra work.