I know people dont like adding chemicals into the tank, but then you have empty tank at the moment. Try AlgaeFX. I used it and it works wonders for the GHA. I have SPS, LPS, softies. No effect on the corals, and the GHA is not visible at all in my DT. I now do weekly water changes of 10% and add a half maintenance dose of AlageFX as recommended on the bottle. Been over 6 months now, no issues and everything doing well and growing. Also running phosphate pellets from Brightwell.
I have used this on my previous tanks, with no ill effects. Read up on it on forums, not many people have issues.
But then again, even with AlgaeFX its a temporary fix to kill off all the current GHA, but you really need to keep the Phosphates and nutrients down for future or your sunlight problem.
Also you can try Algae X from Fauna Marin. i have a brand new bottle, never need to use it. It was my last resort if Algae FX didn't work. This stuff is more potent, and must be used with caution with fish/corals/livestock. I would take out the Purple Tang put it into your QT, and dose the Algae X to the max or even dose a bit more. It really depletes O2, but then again you have no fish or livestock its a great way to eradicate the GHA.
I tried everything. Scrubbing, hydrogen peroxide, lights out (killed some of my corals and fish), less feeding to no feeding (starved my fish).
I have used this on my previous tanks, with no ill effects. Read up on it on forums, not many people have issues.
But then again, even with AlgaeFX its a temporary fix to kill off all the current GHA, but you really need to keep the Phosphates and nutrients down for future or your sunlight problem.
Also you can try Algae X from Fauna Marin. i have a brand new bottle, never need to use it. It was my last resort if Algae FX didn't work. This stuff is more potent, and must be used with caution with fish/corals/livestock. I would take out the Purple Tang put it into your QT, and dose the Algae X to the max or even dose a bit more. It really depletes O2, but then again you have no fish or livestock its a great way to eradicate the GHA.
I tried everything. Scrubbing, hydrogen peroxide, lights out (killed some of my corals and fish), less feeding to no feeding (starved my fish).