My 155 is a 3 weeks running now, it was running when I bought the system. I finished my rockwork a few days ago, found my alkalinity was high(16). The sand, rock, and glass is browning up quick, and the algae is producing bubbles all over the rock. Is this a normal process, are the bubbles just are finding it's way out of the rock, or is there a problem here? My water hasn't been completely stable, as I changed out 1/3 yesterday, and the alkalinity was from overdosing to get calc up, but nitrate, nitrite are very low and no amonia. I lost a couple clowns, and chalked it up to stress from the transfer and rockwork, but now I'm concerned about the fish in there as I'm seeing the same signs that the clowns had the day before they died: a white film developing on his body. Please help.