- Location
- The Big City
You have a lot of fish in a 75gal tank, plus you have 150lb LR and a 3" sand bed which reduces the water volume even more. Also 1 cube of brine shrimp isn't enough for the fish that you have, both quanity and quailty wise.
A bigger skimmer will help, as the Prizm isn't good enough for the load you have in the tank.
You need to reduce your fish population some what and then do some larger water changes in a row. Try doing 25%-35% water changes for 2 - 3 days in a row. That should bring down the nitrates down. Also try cleaning up the tank for any junk or excess algae, do the same in the sump.
When doing the large water changes make sure the new water matches the tank as closely as possible, as not to shock your system.
A bigger skimmer will help, as the Prizm isn't good enough for the load you have in the tank.
You need to reduce your fish population some what and then do some larger water changes in a row. Try doing 25%-35% water changes for 2 - 3 days in a row. That should bring down the nitrates down. Also try cleaning up the tank for any junk or excess algae, do the same in the sump.
When doing the large water changes make sure the new water matches the tank as closely as possible, as not to shock your system.