FIghting velvet algae, limited plant growth
So, by the numbers:
Fluval Spec V
Finnex FugeRay Planted+, 16"
Estimated for 5 gallons of water.
50% weekly water change
3 ml Excel, .75 ml Traces (Plantex CSMB), 1/16tsp Potassium, 1/32 + 1/64tsp Nitrate, 8 drops Phosphates, ⅛ tsp Magnesium.
.75 ml Traces solution, 1/16 Potassium (K2So4), 1/32 + 1/64 Nitrate (KNo3), 6 drops Phosphates (Kh2Po4).
Serve every other day with .75 ml Excel DAILY
I'm using Fleet for the phosphates, No-Salt for the potassium, and potassium nitrate for the nitrates. I have just started dosing magnesium (as epsom salts) here on week 6, but I don't think it's enough magnesium. At water change, the nitrates are at 10, the phosphates are 1.5-2.5 ppm.
Bioload is very light; a king betta, 3 otos, a nerite, and quite a few MTS adolescents. Planted with rotala indica, styrogyne, and marsh clover.
HERE IS THE PROBLEM: I am not getting any red growth. In fact, the growth of the plants themselves seems rather inhibited and I'm getting a lot of velvet algae on the glass and on the plant stems. The marsh clover seems to be doing well, but even it has persistent velvet algae growth. The otos and nerite tend to to a good job getting rid of the algae on the glass and a little on the stems and leaves, but they're not able to completely keep up.
WHAT AM I MISSING? I have been chasing down deficiencies for the last month and I'm not sure where the hole I have to plug is at.