Discosoma not doing well

[Dusko]

Hi all,

I got my self a nice Mushroom coral that looked like this for some time;

Now it looks like this;

Tank stats;
15.8 gallons Nano Reef all in one.
2x18watt 10000K blue-whites
Effective Skimmer 400 l/h.
Circulation pump 680 l/h connected to Hydor BioFlow.
Circulation pump 250 l/h for surface agitation.
All bio filters are removed.

Temp 26'Celsius.
KH7, Calcium 460, NO3 is 2ppm, PO4 is 0.03, NO2 is 0ppm.
Salinity 1.023 SG.
I feed corals every second day with Phytoplankton and Cyclop-eeze.

Water change every second week 10%.
Dosing Salifert All In One every week 2.5ml, every second week Iodine 1ml, Calcium Chloride 1ml 2x a week or when needed.

No algae since the day one except little Green Bubble algae. Lots of Coraline.

Tank pic;

I started using Rowa Phosphate remover lately. Is it possible that this method is removing too much of PO4, leaving nothing for mushrooms?
The Purple Discosoma died totally, but the Rhodactis mushroom is doing extremely well ? (no clue)

Thanks.
Kind regards, Dusko.

 

[rigleautomotive]

they look terrible,and the thing that is puzziling is that they are almost a bullet proof coral.really hardy and hard to kill.it must be water quality.i would ramp up the water changes to 25 or 50 percent weekly and stop adding stuff like iodine or other potentially harmful additives.the water changes are the safest way to see if it is a water quality issue or ionic imbalance.