the hardness in my tak is 1 and i've been trying to get it up to at least 3 for my discus. i use ro/di water and the stuff to get the salts back into the water, "ro right". i also used buffers, but no luck. i used alot more than i should, but the hardness still reads the same. i moved the discus to my new 125 gallons tank and the hardness there is 3 and ph 6.8, but few more fish are going to stay in my old tank and i don't want them to get sick. ph in the low hardness tank is 6.8. what do i do to get hardness up but not too much of ph? i really have no idea what to do. please, help :bowing: