SPS Good Coloration, Slow or No Growth

Nepenthes88 · May 22, 2020

Was hoping to get people's opinions on where to look to solve my good coloration but slow growth issue.

It seems good coloration is relatively harder to achieve than decent growth with SPS and more often people have the problem of decent growth with poor coloration. Is achieving good coloration a precursor to growth and I just need to be patient? Could there be specific factors that are directly holding back growth? Let me know what you think!

My main question: What specific factors could contribute to slow growth despite good coloration?

There's a good chance I'm just being impatient. I've had these specific SPS frags in the tank for just over a month now and the tank is about 5 months old. However, I do have a suspicion that it could be lack of PAR and that I need to bump my lighting set points up.

Tank Specs/Levels

20g L standard aquarium with custom acrylic baffles to create an AIO w/sump area on left side of tank.
Lighting: Reef Breeders Photon V2 24in. (blue channels at 50%, white at 15%, light 12in above water, keep in mind tank is only 12in deep) Could my PAR be too low???
Nitrate: Undetectable (BUT I'm running hybrid Zeovit including using Zeolites, dosing Zeovit Coral Vitalizer, Spongepower, Pohl's Xtra, Zeobak, Brightwell Aminos, NP Bacto Balance as carbon source)
PO4: Steady at 0.03
Alk: Steady at 7.1 (don't test Calcium and MG cuz low consumption and have never added non balanced Alk/CA additives)
Weekly 25% water change

Thanks!

Water

Spare time · May 22, 2020

Take a look at this video

Flippers4pups · May 22, 2020

I've had frags of acropora take a year to settle and start growing with very consistent water parameters and lighting. Some take a while to do this, while others will adapt quicker and take off.

It's a waiting game for sure.

Charlie’s Frags · May 23, 2020

Rent a par meter. Too much can give great coloration but stunt growth, especially if you’re over stripping N/P. I’ve had some of the same struggles. Great color but slow growth. I finally added an apex and discovered my natural ph was 7.6-7.8. So I added a brs co2 scrubber and kalk to my ato. This combo has brought my ph to 8.2-8.5 and I’m seeing new tips sprouting in pieces that have done almost nothing for 9 months. I also turned on my cloud coverage feature to randomly reduce par during my peak photo period.