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My Zoanthids started melting overnight. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate. Tank is a 40 gallon with AI Prime lighting, running for 8 hours a day. Salinity is 1.025, temp at 78. Any ideas what's causing this?

Sounds like your params are solid. Have you checked for pests? Flatworms or nudibranchs can cause Zoanthids to melt. Also, how's your flow? Too much or too little can stress them out.

Yo, I've seen this before. Sometimes it's just a weird vibe with new frags. Did you dip them before adding? If not, could be bacterial. Try a quick iodine dip and see if they chill.

I agree with checking for pests. Also, have you added anything new to the tank recently? Even small changes can mess with Zoanthids. They're pretty sensitive.

Dude, my Zoas did the same thing last week. Turned out my cat knocked over the heater and temp dropped to 70. Sketchy, right? Maybe check your equipment.

seabed wrote: ↑Sun Jul 13, 2025 4:46 pm Sounds like your params are solid. Have you checked for pests? Flatworms or nudibranchs can cause Zoanthids to melt. Also, how's your flow? Too much or too little can stress them out.

Thanks, I'll inspect for pests. Flow is moderate, but I'll adjust it to see if that helps.

rusticfox9 wrote: ↑Sun Jul 13, 2025 8:36 pm Dude, my Zoas did the same thing last week. Turned out my cat knocked over the heater and temp dropped to 70. Sketchy, right? Maybe check your equipment.

Temp swings are brutal. Vaxonix, double-check your heater and maybe invest in a backup. Stability is key with Zoanthids.

If it's not pests or temp, could be a chemical thing. You using any meds or additives lately? Some of that stuff can nuke Zoas if you're not careful.

I've heard of Zoanthids melting from too much light. Maybe dial back the intensity for a few days and see if they recover. They're tough but can be fussy.

My LFS guy said Zoas hate sudden changes. Like, if you moved them or messed with the rockwork, they might just be throwing a fit. Give 'em time.