Corals not extending anymore as some weeks ago

[castellanamattia]

Hi all

My green star polyp (GSP) has not been opening for a few weeks now and my torch coral is retracting the polyps more and more every day. Other corals like Caulastrea furcata, Duncanopsammia axifuga, discosoma and kenya tree (already produced 2x offspring) are doing good in my opinion.

The 20 gal tank is 71 days old and parameters are:
- ammonia < 0.025 ppm
- KH 8.5, nitrate 5
- nitrite 0
- pH 8
- phosphate seems 0 but I dosed 4 ml microbe-lift basic P twice this week, salinity 1.026 sg and temperature 25.3 °C.

As light source I am using an AI prime 16 HD running with saxby preset and acclimation mode starting from 50 % for 30 days. Once a week I dose microbe-lift all in one and nitrate / phosphate if needed

Do you know what's happening in my tank? I know that parameters are still fluctuating, but I don't want to loose my corals.

Thanks!

 

[Mr. Mojo Rising]

I'm not sure if I see any powerheads, do you have any flow?

 

[castellanamattia]

I'm not sure if I see any powerheads, do you have any flow?

Yes I am running a Tunze 6020

 

[PR_nano]

Seems to have a nutrient issue. I would raise phosphate to detectable level especially in newer tank and bump Nitrates more. The brown patches appears to be dinoflagellate.

 

[castellanamattia]

That's what I'm trying to do at the moment. After years of experience with freshwater tanks, I'm kind of hesitant to add too many nutrients to my nano reef. Currently I am measuring my water parameters with JBL tests and phosphate is still undetectable (after dosing twice 4 ml phosphate which would lead around 0.1 mg/l) and in my opinion it is working quite good. Still I am thinking of upgrading to Hanna tester.

Would you add more phosphate tomorrow? Or even increase nitrate levels?

 

[Shirak]

Looks like it's fairly new and Dino's are a PITA. They will really irritate the corals. You can try target feeding the LPS too if you haven't. I would check out the forum on Dinos. / Nuisance Algae