Gut-loading transforms nutritionally-empty live food into a vitamin-rich meal. Why it matters: newly-hatched brine shrimp are 95% water + sugar - they're junk food. After 12-24 hours of gut-loading, their nutritional content matches frozen mysis or pellet food. How to gut-load: 1) hatch baby brine shrimp (24-hour cycle). 2) drain into clean container. 3) add 1-2 drops of phytoplankton (Reef Nutrition Phyto Feast, OceanMagik) or commercial enrichment (Selcon, Selco, Vibrance). 4) wait 12-24 hours at 78°F before harvesting + feeding. For larger live food: daphnia + mysis can also be gut-loaded with phyto + spirulina. Critical for: larval fish + fry, mandarin dragonets, sensitive marine species. Skip for: general community-tank feeding where fish get a varied diet.
Reviewed by the Fast Aquatics husbandry team · Updated May 2026
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