Originally posted by csmall1972
I have two saltwater tanks one 40 gallon and one 55 gallon. I have recently had a problem with both of them. The water has turned green slowly over a week. I have a maximum of two fish in each right now about 3 to 4 inches long (trigger and puffer in the 50and two clowns in the 40. I not sure how to treat this problem.
I highly suspect the green water is suspended algae. As you know algae is plant life and plant life needs carbon dioxde, nutrients (both from your fish), plus light. So by eliminating any of those things the suspend algae would die off and the water would clear up. You could, for instance, turn off your lights for two weeks and the water would clear up. With no other changes the green water would return when you resumed your current lighting.
I would add some desirable plant life (macros or marine plants) to consume the nitrients (ammonia, nitrAtes and phosphates) to starve out the undesirable green algaes. You may have to add a refugium or culture the plants in another container to protect the plants. If you also reduce the lighting and insure you are not overfeeding, the green water will be a thing of the past.