Jim Seidman wrote:

Dave Millman dav.e.at.tac.tics.co.m wrote in message 4...
I am still searching for a good substrate nitrate supplement though.

Is there a reason you feel strongly about keeping the nitrate in your
substrate rather than the water column?

In any case, potassium nitrate (KNO3) is available in granular form at
some garden stores.

I've been dosing KNO3 for 15 months in the water column. Swords are root feeders, and mine do not get what they
need from the substrate or through the water column. Cuck Gadd used pictures of my swords in is talk on Nutrient
Deficiencies at the AGA convention a year ago. These were taken in a tank that got 1.5 tsp KNO3 per week.