I'm sure a lot of people (or no one - maybe I just think a lot) have wondered if saltwater fish flakes are different than freshwater flakes, and if it is or is not safe to use saltwater flakes in freshwater. I know I've looked it up a few times, but there isn't too much information on it. So, I decided to let my fish be the 'test subjects'...as well as myself, myself being if for nothing else but your own entertainment. I am unbiased on these foods and feed them all so my fish have variety, and will simply be reporting what they actually taste like, the ingredients, pricing, and analysis, as well as if my saltwater flake food is safe to use for tropical fish. For the tasting, I will taste one similarly sized flake for the flake foods, and one shrimp pellet. Please keep in mind that I am testing on fish foods fed to most common 'tropical' fish - I may do another test on betta pellets and goldfish food later on. Here is what I have found. Ingredients, pricing, analysis, taste, etc: Name: Aqueon Tropical Flakes Pricing: $2-$5 range for .45 oz. to 1.02 oz. Ingredients: Whole fish meal (herring and other mixed fishes), whole wheat flour, soybean meal, shrimp meal, wheat gluten meal, dried yeast, squid meal, wheat germ, corn gluten meal, dehydrated kelp, fish oil, spirulina, garlic, astaxanthin, marigold powder, chili powder, spinach, choline chloride, L-ascorbyl-2-polyphosphate (source of vitamin C), calcium propionate (a preservative), vitamin A acetate, cholecalciferol (source of vitamin D3), riboflavin supplement, vitamin B12 supplement, Niacin, menadione sodium bisulfite complex (source of vitamin K activity), folic acid, thiamine mononitrate, pyridoxine hydrochloride (source of vitamin B6), calcium pantothenate, biotin, dl-a-tocopherol acetate (source of vitamin E), manganese sulfate, cobalt sulfate, ferrous sulfate, copper sulfate Analysis: Crude protein (min) - 41% Crude fat (min) - 7% Crude fiber (min) - 3% Moisture (max) - 8% Phosphorous (min) - 1% What it tastes like: The taste almost reminds me of a mix of corn flour and fish slime. Each color of flake has a vaguely different taste to it. - Name: Omega One Freshwater Flakes Pricing: $3-$6 range for .42 oz. to 1 oz. Ingredients: Whole salmon, halibut, black cod, whole herring, whole shrimp, whole krill, wheat flour, wheat gluten, fresh kelp, lecithin, astaxanthin, L-ascorbyl-2-phosphate (source of vitamin C), natural and artificial colors, vitamin A acetate, vitamin D3 supplement, vitamin E supplement, vitamin B12 supplement, riboflavin, niacin, pantothenic acid, folic acid, biotin, inositol, tocopherol (preservative), ethoxyquin (preservative) Analysis: Min. crude protein: 41% Min. cride fat: 12% Max. crude fiber: 2% Max. Moisture: 8.5% Max. Ash: 8% Min. Phosphorous: (.5%) Min. Omega 3: 2% Min. Omega 6: 1% What it tastes like: Same as Aqueon Tropical Flakes; however, the taste is more vague. - Name: Wardley Shrimp Pellets Pricing: $3-$6 for 4.5 oz. Ingredients: Shrimp meal, wheat middlings, fish meal, dehulled soybean meal, fish oil, lignin sulfonate, L-ascorbyl-2-polyphosphate (source of vitamin C), rice hulls, choline chloride, betaine, ethoxyquin (a preservative), vitamin E supplement, calcium carbonate, menadione sodium bisulfite complex (source of vitamin K activity), zinc proteinate, zinc sulfate, niacin supplement, biotin, calcium pantothenate, riboflavin supplement, pyridoxine hydrochloride, manganese sulfate, manganese proteinate, vitamin A supplement, sodium selenite, Vitamin B12 supplement, folic acid, copper sulfate, copper proteinate, vitamin D3 supplement, calcium iodate Analysis: Crude protein (min): 36% Crude fat (min): 8% Crude fiber (max): 6.5% Moisture (max): 11.5% Phosphorus (min): 1.2% Ascorbic acid (min): 400 mg/kg What it tastes like: This one tastes like fish slime mixed with your stereotypical 'medicine' flavor. - Name: V-Pure Marine Fusion Pricing: $6.99 for 0.7 oz. Ingredients: Brine shrimp, krill superba, krill pacifica, mysis shrimp, squid, mussels, wheat flour, seaweed, soy protein, salmon egg oil, blood meal, lecithin, calcium chloride, magnesium sulfate, vitamin premix (ascorbic acid, stabilized vitamin C, dl-alpha tocopheryl acetate, d-pantothenic acid, riboflavin, niacin, menadione, folacin, cholecalciferol, biotin, thiamin, retinol, pyridoxine, and cyanocobalamin), select amano acids (arginine, histidine, isoleucine, leucine, lysine, methionine, cystine, phenylalanine, threonine, tryptophan, and valine), carotenoid pigments (canthaxanthin and/or astaxanthin), artificial color, and preservative (ethoxyquin) Analysis: Crude protein (min): 60.2% Crude fat (min): 11.2% Crude fiber (max): 3.5% Moisture (max): 5% Total omega3 fatty acids: 3% Vitamin C per kg. 1,000 IU What it tastes like: This one tastes like fish slime mixed with a vegetable of some sort (maybe it's the seaweed?) - End result of two week long experiment: Platys and guppies had no preference for a fish food brand. They ate it all with the same gusto - they went for the flakes before the pellets, however. Honey gourami only likes flakes. Cherry barbs were 50/50 on if they liked the pellets or flakes better. Corydoras obviously only ate the pellets. Shrimp don't care one bit. The marine flakes that I used did not harm or kill my fish, shrimp, or scuds. I feel confident enough to keep using them in my freshwater tanks as a rotated food. From what I have researched, the main difference between marine flakes and freshwater flakes is that marine flakes are much lower in phosphorus. Obviously this brand is also higher in protein, as well, compared to the listed freshwater flake foods, so this will need to be considered for the particular fish you are feeding. I hope that this helps someone, or is entertaining at the least. To anyone wondering, yes, I did have drink on standby.