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My Acropora has been in the tank for about 3 months now, and it's not branching like I expected. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate, 8.2 pH, 420 calcium, 1300 magnesium. Running a Red Sea Reefer 250 with Radion XR15 lights at 60% intensity. Any ideas what's up?

Sounds like your params are solid, but Acropora can be picky. How's your flow? They need random, turbulent flow to thrive. I'd also check your alkalinity, it's not listed. Stable alk is key for growth. What's your dosing routine like?

Yo, my Acropora did the same thing till I cranked the flow. Got a couple MP40s now and they're finally branching. Maybe your tank's too chill? Also, what salt mix you using? Some are sketchy for SPS.

rockel wrote: ↑Fri Aug 29, 2025 2:16 pm Yo, my Acropora did the same thing till I cranked the flow. Got a couple MP40s now and they're finally branching. Maybe your tank's too chill? Also, what salt mix you using? Some are sketchy for SPS.

Flow is definitely a factor, but let's not overlook lighting. SilverAce, how long are your lights on each day? Acropora need 8–10 hours of intense light to trigger branching. Also, what's your phosphate level? Too low can stunt growth.

I had this issue too. Turned out my alk was swinging too much. Started dosing daily and saw improvement in a few weeks. Maybe check your alk stability over a week?

Agree with the flow and alk comments. Another thing to consider is trace elements. Are you dosing anything like strontium or iodine? My Acropora took off when I started adding them. Also, how often are you feeding? They need some amino acids to grow.

My Acropora didn't branch till I switched to Tropic Marin salt. Maybe your salt mix is missing something. Also, what's your temp? Stable 78–80 is ideal.

flamur wrote: ↑Fri Aug 29, 2025 8:30 pm My Acropora didn't branch till I switched to Tropic Marin salt. Maybe your salt mix is missing something. Also, what's your temp? Stable 78–80 is ideal.

Haha, salt mix drama is real! But seriously, temp swings can mess with growth. SilverAce, you got a controller on that heater? Also, how old are your bulbs? Radions lose intensity over time.

My Acropora was stuck till I added more fish. The extra nutrients helped. Maybe your tank's too clean? What's your bioload like?

Thanks for all the suggestions, everyone. I'll check my alk stability and maybe tweak the flow. Running two Nero 5s right now, but might add another. Also gonna test phosphates and look into trace elements. Appreciate the help!