For coleb... I'm going to take a different approach I'm very new to salt water and aquariums in general... my tank has been set up for 3 years and I have had the same issue as you. bought a Duncan head 2 years ago and till recently a friend suggested that I would check alk more often sure enough it was on the low side at 7... it had been at 7 for ever but when I raised it up in a few months it started to grow... so check on that I know there will be lots of ppl stating that stability is the name of the game and I follow that till now... but keep in mind if u r going to raise it do it slowly to dramatic of a change and so will many ppl tell you is a recipe for disaster. I hope it helps I'm still learning.