[Timfish]

+1 on PO4 is too low.

Here's some experiements done with corals in a ULN system. PO4 deficiency really messes up the coral/zooxanthellae simbiosis

http://www.indiaenvironmentportal.or...enrichment.pdf
https://www.frontiersin.org/articles...015.00103/full
https://www.sciencedirect.com/scienc...601?via%3Dihub

And here's a video by Fichard Ross ar MACNA 2014 on phosphate:

https://www.youtube.com/watch?v=ZRIKW-9d2xI


(Here's a mole/gram converter if needed:
https://www.chemicalaid.com/tools/mo...weight=&moles= )