large water changes along with more water circulation , ease up on feedings . a turkey baster works great for blowing off the rocks and you can lightly blow the sand surface while running a siphon .
You'll need to find the source of where the excess nutrients are coming from and fix it, Are you using tap or RO
water have you tested your water source for nutrients
what do your parameters look like.
how long has the tank been set up , the first 6 months is the big hurdle but it's up to you to get through it by maintaining your tank and keeping up with it . things will get better in time so just hang in there.