Ok just give them some time off of food like previously stated and your tank should return to normal. Also change your food, aqueon food is crappy (I've found this out through experience) and Tetra Min plus has always worked overtime for me. All my fish (except my BGKF he won't eat anything but meat) love tetra min plus so consider getting some more high quality and expensive foods. My reccomendations...a combo of Tetra Min as main food, New Life Spectrum as a treat and Omega one as another treat. I use all of those foods and I have absolutely no complaints about any of them.
The ingredient list in Aqueon or Tetra is no better than any other low end food which uses alot of grains such as corn, wheat, and oat flour which serves as low grade proteins, fillers, and binding agents. Look at their list and then compare to NLS flakes which uses actual whole Antarctic krill and whole hearing instead of fish meal which utilizes all the left over parts from other industries rather than the whole fish. The type and origin of proteins will have a drastic effect in digestion in which most people with fish should be concerned with.
NLS:
Whole Antarctic Krill Meal, Whole Herring Meal, Wheat Flour, Whole Squid Meal, Mussel Meal, Algae Meal, Garlic, Soybean Isolate, Beta Carotene, Spirulina, Vegetable and Fruit Extract (Spinach, Broccoli, Red Pepper, Zucchini, Tomato, Pea, Red and Green Cabbage, Apple, Apricot, Mango, Kiwi, Papaya, Peach, Pear), Ginseng, Vitamin A Acetate D-Activated Animal Sterol (D3), Vitamin B 12 supplement , Thiamine, Biotin, DL-Alphatocophero (E), Riboflavin Supplement , Niacin, Folic Acid, Calcium Pantothenate, Pyridoxine Hydrochloride, L-Ascorby-2-polyphosphate (Stable C), Choline Chloride Ethylenediamine Dihydroiodide, Cobalt Sulfate , Copper Proteinate, Manganese Sulfate, Ferrous Sulfate.
Tetra:
fish meal, dried yeast, ground brown rice, shrimp meal, wheat gluten, feeding oat meal, fish oil, potato protein, dehulled soybean meal, soybean oil, algae meal, sorbitol, lecithin, monobasic calsium phosphate, ascorbic acid (source of vit. C), yeast extract, inositol, niacin, L-ascorbyl-2-poolyphosphate, riboflavin-5-phosphate (source of vit. B2), A-tocopherol-acetate (source of vit. E), D-calcium pantothenate, thiamin mononitrate (source of vit. B1), pyridoxine hydrochloride (source of vit. B6), vitamin A palmitate (source of vit. A), menadione sodium bisulfite complex (source of vit. K), biotin, cyanocobalamin (source of vit.B12), cholecalciferol (source of vit. D3), manganese sulfate monohydrate, zinc sulfate monohydrate, ferrous sulfate monohydrate, cobalt nitrate hexahydrate.
Tetra, Aqueon, and Wardley's are absolute junk not fit for consumption, here is their proteins(heads, lips, and backsides) which are left over bi-products from other industries.