how much food do I feed?

[yukon tang]

75 gal. tank-1 yellow tang-2 perculas-lawnmower blenny-scooter blenny-coral beauty-5 chromis-1 mandarin-yellow tail damsel- 3 skunks-2 peppermints-2 feather dusters- starfish. I have a cascade canister filterfor my size tank(700-!000? model).They say my algea woes are too much feeding-but no one says how often or much to feed-help-everything seems happy otherwise-phosphates and nitrates always a little high but within no panic mode. have sponges and coral growing too-can i add a nother filter canister-would it help

 

[katz]

I feed mine, half a cube of varies types of frozen food a day.
2- chromis
2- black and white clowns
1- bi color blenny
1- flameback angel
1- fliminda(sp ?)
1- yellow goby
1- diamond back goby
1- cleaner shrimp
1- fire shrimp
Katz :happyfish