Have been fairly successful in getting rid of green water using info from
info from Tom Barr on our 215 gallon tank. Stats a

Iron - 0.1 ppm (never has been anything else but)
pH - 7.0 (controlled by Dupla auto-CO2 system)
Ammonia - 0
Nitrite - 0
Nitrate - keep between 5 and 10 ppm (adding 1.5 tsp 2x a week or more often
if falls below per Tom Barr)
KH - 10 degrees
Total Hardness - 120 ppm
Total Alkalinity - 300 ppm
Phosphate - 0.5 (after adding 1/8 tsp 2x a week - per Tom Barr)

I know that KNO3 should be between 6-7 ppm (Tom Barr). I can't seem to find
out from anywhere what is the target PO4 I am shooting for? Also, I am
adding PO4, not K2PO4 as Tom indicated. Should I also buy Potassium? And
if so, what is the target level for that?

Are any of my stats the reason for the red jungle val to loose their leaves
as soon as they become red? or that they are all getting krinkled? Also my
once beautiful cryptocorynes and getting pale on the leaves except for the
leaf veins are bright green? I'm getting all algae under control now except
for some hair algae.

Thanks in advance for all you help. This site really has helped us keep
progressing on this tank.

Belle/Vernon