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What's the ideal temp range for a mixed reef tank? I've got Zoanthids, Acros, and a few LPS like Hammers. My tank's been sitting at 78°F, but I've heard some folks push it to 80°F for growth. Running a 75-gallon with dual AI Primes, 1.026 salinity, and weekly 10% changes.

I keep mine at 77°F, seems to work fine. Got a bunch of softies and a couple SPS frags. Tank's only 40 gallons though, so maybe smaller systems chill better. Using a cheap heater, but it's steady.

aquaguru wrote: ↑Tue May 06, 2025 8:39 pm I keep mine at 77°F, seems to work fine. Got a bunch of softies and a couple SPS frags. Tank's only 40 gallons though, so maybe smaller systems chill better. Using a cheap heater, but it's steady.

Smaller tanks can swing faster, so 77°F makes sense. For a 75-gallon like OP's, I'd lean 78–79°F. My mixed reef's at 78.5°F with Red Sea salt, and everything's happy. Torches especially dig it.

78°F is solid! My LFS swears by 79°F for SPS, but my LPS started retracting at that temp. Bumped it down to 78°F, and they perked up. Maybe it's the brand of heater? I'm using a Cobalt Neo-Therm.

Y'all overthink it. 77–80°F is the sweet spot, full stop. My mixed tank's been at 79°F for years, no drama. Just keep it stable—wild swings mess with their vibe. Running a 120-gallon with T5/LED hybrid, and even the picky Acros are growing.

Thanks for the input! Gonna stick with 78°F for now and watch how the Hammers react. Appreciate the heater recs too.

Stability's key, like BoldOne said. If you're gonna tweak it, do it slow—maybe 0.5°F per day. Also, what's your alk sitting at? High temps can mess with consumption rates.

foxlyn wrote: ↑Wed May 07, 2025 3:02 am Stability's key, like BoldOne said. If you're gonna tweak it, do it slow—maybe 0.5°F per day. Also, what's your alk sitting at? High temps can mess with consumption rates.

Good point! My alk's at 8.5 dKH, and I dose daily. Temp swings definitely threw it off last summer when my AC died.

Summer's the worst. I had to add a chiller after my tank hit 83°F one July. Corals looked pissed for weeks. Now I keep it at 79°F year-round, no excuses.