Phosphate issues... the bad and some good

[Koty]

1. GFO is out of the system.
2. Did not replace filter wool for about 4-5 weeks.
3. NO3 is too low (I started dosing Amino acids (TM also).
4. stopped dosing "trace elements" (TM A & K elements).
The rise in Alkalinity probably signifies that the rise in PO4 may slow growth. However, the corals look very happy including the few SPS corals that I have. A bigger problem is green hair algae that used to show up occasionally, but now it is all over the tank and seems to start threatening the corals. I started dosing amino acids (TM) to keep the NO3 above 0. I am reducing the amount of fish food and plan to add back GFO. CUC are out of the question as are not allowed. I have a Scopas that eat some of it but it is far from having any effect.

 

[Koty]

The first lines were cut somehow:
I wanted to share my experience with trying to control phosphate in a high-bioload tank (many corals and many fish). My tank is over 3 years old and After getting the GFO reactor out, my phosphate started to creep up. I also started to get a lot of green hair algae. GFO went out because I do not like that the silica is taken out of the system as I do not do water changes.

 

[Pod_01]

Out of curiosity what do you feed your fish? From my experience I observed that some fish foods lead to imbalance and PO4 increase. Also having too efficient NO3 removal mechanism (like fuge etc..) can lead to increase in PO4. The organisms need NO3 to help with PO4 removal.
With feeding I had more luck using Fauna Marin Soft multi mix pellets. I used to feed frozen, home made and pre made and ended up with elevated PO4. Nothing wrong with frozen but it didn’t work for my tank.

My PO4 stays around 0.1-0.2ppm and NO3 is 1-5ppm. I don’t use GFO or fuge, floss, socks etc… to manage PO4 or NO3.
I do feed about 4 times a day and have 7 fish so there are plenty of pellets floating around with each feeding. For filtering I only use skimmer.

Looking at your photo you should have sufficient coral mass to help with the PO4. Maybe your other NO3 removal methods are too efficient. Use of numerous nutrient export methods can hide other issues and that is why I slowly discontinued use of all of them.
Idea being the corals are the main filter method and other methods can be used to supplement if required.

Also amino can promote growth of undesirable so that might be feeding your GHA.

Good luck,

 

[Koty]

I do feed frozen mysis, krill and blood worms on top of TDO/Hikari dry pellets. I have a copperband and so a fresh mussel every day. I will clearly reduce the frozen part but the CBB does not eat anything but mussels and bloodworms. I add Tropic Marin “Amino-organics” which also has other nitrogen containing compounds.
Thanks