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I've been breeding Discus for a while now, but my fry keep dying within a few days of hatching. The parents seem healthy, water params are good, 0 ammonia, 0 nitrite, nitrate around 10 ppm. Temp is 84°F, pH 6.5, and I'm doing daily 20% water changes. Tank is bare-bottom with a sponge filter. Any ideas what's going wrong?

That's rough, sorry to hear it. Have you checked the parents' diet? I had a similar issue until I started feeding mine more live foods like blackworms and brine shrimp. Also, are the fry getting enough infusoria or baby brine shrimp right after hatching? They're super tiny and need microscopic food at first.

sealine wrote: ↑Thu Aug 07, 2025 2:26 am I've been breeding Discus for a while now, but my fry keep dying within a few days of hatching. The parents seem healthy, water params are good, 0 ammonia, 0 nitrite, nitrate around 10 ppm. Temp is 84°F, pH 6.5, and I'm doing daily 20% water changes. Tank is bare-bottom with a sponge filter. Any ideas what's going wrong?

Your setup sounds solid, but fry are super sensitive to even tiny parameter shifts. Are you matching the temp and pH exactly during water changes? Also, how old are the parents? Younger pairs sometimes struggle with fry care.

Oh no, that's so frustrating! I've been there. Have you tried adding almond leaves? They release tannins that mimic their natural habitat and might help the fry feel more secure. Also, are the parents eating the fry? Sometimes they get stressed and snack on them, especially if the tank's too bright or there's too much activity around it.

Could be a bacterial issue. Even if your params are perfect, fry tanks can develop harmful biofilms. Try wiping down the sides daily with a clean cloth and maybe add a tiny bit of methylene blue as a preventative. Also, how's the flow from the sponge filter? Too strong and it'll tire out the fry.

Thanks for the suggestions, everyone. I'll try adding almond leaves and upping the live food for the parents. The flow's pretty gentle, but I'll double-check. Parents are about 2 years old, so they should be mature enough. I'll report back in a few weeks!

Yo, sounds like you're on the right track. Just gonna throw this out there—you sure the sponge filter's cycled? Even if it's been running, fry tanks sometimes need a kickstart. Maybe toss in a pinch of fish food to boost the bio load gently. Also, keep the lights low-key, fry get sketched out easy.

guppy wrote: ↑Thu Aug 07, 2025 3:39 am That's rough, sorry to hear it. Have you checked the parents' diet? I had a similar issue until I started feeding mine more live foods like blackworms and brine shrimp. Also, are the fry getting enough infusoria or baby brine shrimp right after hatching? They're super tiny and need microscopic food at first.

Seconding the food angle. If the fry aren't eating within 48 hours, they'll starve. Try hatching your own baby brine shrimp—store-bought stuff can be hit or miss. Also, what's your water change routine? Too much too fast can shock them.

Aight, real talk—you checked for pests? Hydra or planaria will wreck fry. If you spot any, nuke 'em with fenbendazole. Also, how's the tank placement? If it's near a window or a busy area, the vibrations might stress the parents into eating the fry.

Had this exact issue last year. Turned out my tap water had trace copper from old pipes. Even though it tested safe for adults, the fry couldn't handle it. Switched to RO water with a remineralizer and boom—next batch survived. Maybe grab a copper test kit just in case?