I purchased a nitrite test kit by salifert. I have a hanna ULR Nitrite checker that taps out at (200ppb) .2ppm and flashes when it's even higher. It's a new tank in cycling. The powder came as a rock so I broke it down and shook it so it mixed up and did a test but it Didn't color the sample at all. Expiration is 7/22. Tested with TPI and I believe its in between .25 and .5. Is it normal for the powder to come as a rock?