I tried all the above too...more circulation, different bulbs, turned lights off 3 days, switched to RO water, water changes, etc, etc, etc.
Used this and it was gone. Be conservative on dosing (eg remember rock displaces water so even if you have a 55g tank, you don't have 55 g of water in many cases). Watch how everything reacts, be ready with water changes as directed. But otherwise it worked fine and I had the motivation to continue in the hobby.
I was about ready to throw in the towel. IMO, if you have reached the point of total frustration and are about to give up, use this product for sure.