how to prevent a algae in salt fish tanK?

[Megalodon]

Originally Posted by jhoepopoy

my tank is 29G w/ HOB CPR BAK PAK 2 protein skimmer , T5 4bulbs, 40pound sand, around 15 to 20 lbs liverock, two clown fish, 2 yellow damsel, 4 hermit crab, 1 cleaner shrimp and 2 snails my is tank is 4 weeks right now!!!

Was the liverock cured or uncured when you added it? You may need to check ammonia. If any is detectable you will want to do small water changes.