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I am referring back to my recent post when my Naso and Tomini became sick and died within 24 hours of eating Emerald Entree frozen food. I contemplated every other option and I am very certain it was the food. I was so tragic and sad. In my research, I have found that it does happen. If you look at the photo, look at the warning "Do NOT THAW" in huge writing on the packaging. Also here is some of my research that might interest people. I better give everything the extreme smell test!
Yes, frozen fish food can become toxic and kill saltwater fish if it's spoiled, contaminated (bacteria/parasites), improperly thawed (left out too long), or refrozen, leading to food poisoning or introducing pathogens, though high-quality, properly handled frozen food is generally safe and nutritious. Key risks are bacterial blooms from thawing/refreezing and potential contaminants from the source, so always thaw in the fridge/cold water and use immediately.
This video explains the pros and cons of different types of fish food:
46s
Bulk Reef Supply - Saltwater Aquariums
YouTube • Nov 12, 2021
When Frozen Food Becomes Toxic:
46s
Bulk Reef Supply - Saltwater Aquariums
YouTube • Nov 12, 2021
How to Avoid Problems:
Yes, frozen fish food can become toxic and kill saltwater fish if it's spoiled, contaminated (bacteria/parasites), improperly thawed (left out too long), or refrozen, leading to food poisoning or introducing pathogens, though high-quality, properly handled frozen food is generally safe and nutritious. Key risks are bacterial blooms from thawing/refreezing and potential contaminants from the source, so always thaw in the fridge/cold water and use immediately.
This video explains the pros and cons of different types of fish food:
46s
Bulk Reef Supply - Saltwater Aquariums
YouTube • Nov 12, 2021
When Frozen Food Becomes Toxic:
- Spoilage: After thawing, bacteria multiply rapidly. If left out for hours or refrozen, it can cause serious illness, say humble.fish users and DRP Aquatics.
- Bacterial Contamination: Improper handling (not rinsing well, leaving thawed food in water) can introduce harmful bacteria into the tank, especially for sensitive corals and fish.
- Parasites/Pathogens: If the original source wasn't clean or the freezing process was interrupted, parasites or bad microbes can survive and affect your fish.
- Elemental Buildup: Foods with high levels of elements like copper (if not rinsed) can slowly poison reef tanks over time, though this is a long-term issue, say this YouTube video and this other YouTube video.
46s
Bulk Reef Supply - Saltwater Aquariums
YouTube • Nov 12, 2021
How to Avoid Problems:
- Thaw Safely: Thaw portions in the refrigerator or in a container with cold tank water, not at room temperature.
- Use Immediately: Once thawed, use it within minutes; never refreeze, warns San Francisco Bay Brand.
- Rinse (Optional): For fish-only tanks or to reduce nitrates/phosphates from the packing liquid, rinse food like mysis shrimp in tank water before feeding, say DRP Aquatics users and this YouTube video.
- Inspect: Discard any food that smells bad or seems off, notes San Francisco Bay Brand and Humble.Fish users.
- Vary Diet: Combine frozen food with high-quality pellets/flakes for balanced nutrition, say DRP Aquatics users and this YouTube video.
