What am I doing wrong?

[Max93]

Difference!

 

[Yanir34]

Hello,

I’m looking to establish a dominant acropora reef, and my “tester corals” which are two green slimers and a red monti aren’t doing great. They were doing awesome in quarantine though! Same light, same salt mix, just smaller tank. Quarantine is ten gallons.

My tank and specs:

220g with sump
220 int reef octopus skimmer (running on lowest setting, skims out some serious skimmate)
10 fish
Various LPS that are doing good and zoas
Hydra 26 lights (four, two pucs on each)
I run chemipure blue (two big bags, rated for 75 gallons each bag so I’m doing under recommended amount)
Temp 77
BRS AB+ light setting, no modifications.
two icecap 4K gyres
Tank is now 9 months old, added acros at 8 months once I noticed parameters were stable.
Filter socks changed weekly or when clogged

parameters:

using salifert, and refractometer for SG at 1.026

alk: 8.0
Mg: 1200
Ca: 400
Nitrates: 5

it doesn’t matter when I test, it always is the same and I test every other day almost. I use an Auto doser.

I feed about two to three cubes of food a day, broadcast feed every time and also dose a bit of oyster feast.
My tank has zero algae anywhere other than what grows on the glass that I use magnet for.

the problem:

my slimer has burnt tips. Polyps are not as big and fluffy as they used to be in the quarantine tank.
Is my issue phosphates? It’s the only thing I haven’t tested..

I’ve been in this hobby for over 15 years and I’ve never been able to successfully grow acros. I got this massive tank in hopes that I was having issues due to nano tanks.

please let me know if you have questions, and thank you for helping !!

you should be checking your no3 and po4 with good realibe checker's like HANNA Ultra low for po4 , and salifert for no3 .
also check your par levels , acropora like the range of 200 to 350 par, although I run my sps with 400 to 500 .

 

[Max93]

you should be checking your no3 and po4 with good realibe checker's like HANNA Ultra low for po4 , and salifert for no3 .
also check your par levels , acropora like the range of 200 to 350 par, although I run my sps with 400 to 500 .

Check! This has all been accomplished now.