why are my corals not growing?

[Bolton]

My corals aren't growing, and I'm not sure why. I've got a 40-gallon tank with a Radion XR15 light, running 8 hours a day. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate, 8.2 pH, 1.025 salinity. I feed them Reef Roids twice a week. Tankmates are two clownfish and a cleaner shrimp. Substrate is CaribSea sand. Any ideas?

[flyby_1]

Sounds like your setup's pretty solid. How old's the tank? Sometimes they take a minute to settle in. Also, what's your alk and calcium at? If those are off, it can mess with growth big time. I'd test those next if you haven't already.

[tigron]

Yo, same thing happened to me last year. Turned out my light was too weak. You sure the XR15's enough for a 40? Might wanna crank it up or add another. Also, how often you do water changes? I slack on those and my stuff stops growing.

[calanta]

My corals aren't growing, and I'm not sure why. I've got a 40-gallon tank with a Radion XR15 light, running 8 hours a day. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate, 8.2 pH, 1.025 salinity. I feed them Reef Roids twice a week. Tankmates are two clownfish and a cleaner shrimp. Substrate is CaribSea sand. Any ideas?

Your light's fine for softies and LPS, but if you're trying SPS, you might need more intensity. Check your alk (8–9 dKH), calcium (420–450 ppm), and mag (1350–1400 ppm). Also, Reef Roids are good, but try adding amino acids. They're a game-changer for growth.

[deepwave]

Could be flow too. What's your powerhead situation? If they're not getting enough movement, they might just chill and not grow. I run two Nero 5s in my 50 and it made a huge difference.

[Bolton]

Thanks for the tips, everyone. I'll test alk and calcium today. Tank's about 6 months old, by the way. Flow's from a MP10 at 70%. Maybe I'll bump it up.

[flyby_1]

Thanks for the tips, everyone. I'll test alk and calcium today. Tank's about 6 months old, by the way. Flow's from a MP10 at 70%. Maybe I'll bump it up.

Six months is still young. They might just need more time. But yeah, testing alk and calcium is key. Let us know what you get.

[tigron]

For real, time helps. My tank didn't really pop until like 9 months in. Also, you dosing anything? I started with Brightwell's stuff and saw growth in weeks.

[calanta]

For real, time helps. My tank didn't really pop until like 9 months in. Also, you dosing anything? I started with Brightwell's stuff and saw growth in weeks.

Dosing can help, but only if your levels are off. Test first, then dose. Blind dosing's a sketchy move. Also, what corals you got? Some just grow slower.

[deepwave]

True on the coral types. My Zoas took forever to spread, but the Acans? They blew up fast. Patience is key, but testing's your best friend.