firstly your expensive baking soda should be kept away from heat or moisture & completely sealed to maintain a lable claimed product.
secondly i know you let the water sit, but do you mix this stuff & add straight away, or drop it in you jug when you purchase the water & there it sits?
your waters satuation level would easily be able to absorb 1/4 tsp in 5 gal.
maybe if your water was freezing it would only slowly desolve, but im gathering your not that silly.
if its all you mixing, add it to a 3lt coke bottle with an adjustable dripper. add & shake the
sh#t out of it. that should ease your problem of any flakes not desolved. If you have sensitive animals it can pose a problem with random settlements from you jug.
even if you love that jug, id suggest you drop a small & cheap power head in there till your ready as a matter of course. water shouldn't be still for one, & it will definately desolve your snowflakes. If theres still chunks, its not meant to be in the tank.
