12 species-specific food buying guides. Each guide covers diet type + feeding frequency + brand picks across budget tiers + what to avoid.
Single-food diets are the #1 nutritional cause of aquarium fish death after water quality. A pellet-only diet over months leads to vitamin deficiencies (especially HUFA omega-3s for marine fish), reduced immune response, and Hole-in-the-Head disease in cichlids + tangs. The fix is rotating 3-5 different foods across each week.
The protein-fat-fiber-vitamin balance varies dramatically across species. Carnivores (oscars, large cichlids, predator marine fish) need 40%+ protein, low fiber. Herbivores (tangs, mollies, plecos) need under 30% protein, high fiber + algae. Omnivores (clownfish, gouramis, most tetras) sit in between. Misfeeding bloats herbivores + starves carnivores.
For meal-by-meal planning, see our feeding schedules by species, calculator library, and coral feeding guide.
How often should I feed? Once or twice daily for adults; 3-4 times daily for fry. Skip feeding 1 day per week for adult fish - it improves digestion + reduces obesity.
Frozen vs pellet vs live? Use all three. Pellet for the convenience baseline (60-70% of meals). Frozen mysis/bloodworms 1-2x weekly for variety + protein. Live (brine, blackworms, daphnia) for finicky species + breeding conditioning.
Why won't my fish eat the food I bought? 3 reasons: water quality is bad (test first), the fish is stressed from a recent move (give 3-5 days), or the food is wrong for its diet preference. See why is my betta not eating + diagnoser.
How long does food last? Pellets: 12-18 months sealed, 4-6 months opened in dry storage. Frozen: 12 months in deep freezer. Live cultures: indefinite if maintained.
Should I gut-load live food? Yes for finicky species or fry. Gut-loaded brine (with selcon or phyto) is dramatically more nutritious than plain brine. See gut-loading glossary.
Best food guides by species · Feeding schedules · Copepod culture · Phytoplankton culture · Live food culturing · Coral feeding techniques · Q&A library · Glossary