There is no Hanna nitrate test, they do have a nitrite checker.
You guys are tempting me. My tank is a re-build after a move and has been set up 11 months. My SPS is doing pretty well. Some have great color, some are so-so. No bleaching problems at all. I have 9 fish including a fairly large purple tang. Feed 1-2 cubes Hikari mysis, approx 2 cube equivalent of LRS daily and 1/2 sheet of nori 4 days/ week. Tank is 72x24x21, total water volume with sump is approx 160 gallons
Parameters: pH 8.15-8.3, Calcium 410, Mg 1400, Alk 8.0, Nitrates undetectable (Red Sea/Salifert), PO4 0.01-0.03.
I have zero algae problems but do have a heavy biofilm on the glass requiring cleaning every other day.
If I start dosing NO3 am I going to have algae issues? Will it affect the biofilm issue I'm having?
I don’t think you will have algae issues with it but I couldn’t speak scientifically on whether it will directly affect your biofilm. I actually started to feed heavy instead of dosing KNO3 and it’s caused a a bacterial bloom as well as a film on the glass. I think you could stand to either get more fish if feeding that heavily or start dosing KNO3. I’ve heard people say that fish poop gives better colors than dosing potassium nitrate but I saw some pretty great colors using the stuff and so far trying to balance it out naturally has caused me issues. I would give it a shot. You might be able to cut your feeding in half.