I have a reef tank. I just added my first fish, a valentini puffer. After having him in the tank for more than a week, the nitrates suddenly spiked to 10. (They were around 0-2.) In the past three days I have done three five gallon water changes trying to clean out all of the filtration and dilute the nitrates. My tank is a 30 with a ten gallon sump/refugium. After the first change the nitrates fell to 5, but I can't get them any lower. (Even with two more water changes and scrubbing out the bio balls and power heads.) I think the nitrate level is why all of my montiporas are not extending their polyps.

A few things have changed also. Four days ago we had to switch our lighting hood (the other one caught on fire). Still using the same T5's though. The other thing is that the hair algae in my tank is taking over! It's everywhere! I am trying to pull it out by hand.

Does anyone have any advice for me?

Thanks!