Water changes are the best thing you can do (50% twice a week until you get ammonia under control). I'd just use the Ammo Lock according to instructions. Leave the filter alone unless it is collecting a lot of gunk. If it is, just rinse it off and put it back in filter and reduce feeding. If you don't already have them, adding a few bunches of fast growing stem / floating plants will really help with the ammonia. Don't know how big your fish are, but all except the mollies will require a larger tank. You could be fighting a losing battle if the fish are good size.
The water changes and addition of the plants are probably the two most important things you should do in the short term. In the long term, take a look at the fish profiles provided here on the site and try to adjust your stocking with fish that are appropriate for a 30 gallon and share similar water and condition requirements.
Best of luck.
The water changes and addition of the plants are probably the two most important things you should do in the short term. In the long term, take a look at the fish profiles provided here on the site and try to adjust your stocking with fish that are appropriate for a 30 gallon and share similar water and condition requirements.
Best of luck.