New to hydro, sprout has spots. (Pic)

Depends on the plant and how much they eat. 2000 seems pretty high to me though. I run 800-1200.

EDIT. And yes. TDS is TDS Total dissolved solids. Regardless of the volume of water.

CH?

i have an aerogarden make sure it is not in germ mode i think cannabis needs more than that provides.

If you mean PH, here is a chart