One year nano suddenly doing poorly

[NotReefsafe]

A year ago I started my first tank--15g nano. All was well for about 8 months, then I started battling with some huge GHA issues. I started feeding less, water changing more. Then, a few weeks ago, corals starting going south. I recently lost a torch and an alve. Surviving corals are looking terrible.Other corals are alveopora, mushrooms, Duncan, zoas, leather. The alveopora that died was thriving for 6ish months.

Params tested by LFS

Alk 10.36
pH 7.1
Phosphate .9
Calcium 539
Mag 1294
Nitrate 7

Seems to me pH is quite low....

I don't think after 4 months, GHA suddenly killed my alveopora and made others unhappy. Something more at play here, not sure what.

 

[blaxsun]

0.9ppm is fairly high for phosphates (unless this is a typo). And yes, pH is also low (though this will vary over a 24-hour period).

 

[NotReefsafe]

ok, thanks!

 

[Science/G]

Maybe try some rowaphos in a mesh bag and get those phosphates down to .02 to .1