Chemicals are really not the answer. Start with the water changes right away.
What do you have in your tank now?
What size tank do you have?
Information like this will help people here be able to help you better.
Protein skimmer IMO
is a must.
First start with the water changes immediately.
Post back with the rest of your water parameters
125 Gal-35 Gal Wet/Dry-Tetra-Tec PF500 HOB
(3) AuquaClear 301 Powerheads-600 GPH
Automatic Tempature Controller
5-6 Inch Sand Bed-200+ lbs of LR