i have a 30 gallon, low tech planted tank and for the past month, i've been having a low pH reading, around 6.0. i've tested every rock and equipment, thinking something new i put in affected the pH. but everything i tested yielded a reading of 7.0, which is the same reading as the tap. i've been constantly changing the water a little bit at a time. ammonia and nitrites are at 0ppm, while nitrates are around 5ppm (i know its on the low side for a planted tank due to the constant water changes, but i figured i should correct the pH problem first before being too worried about the plants) the fish dont seem to affected, as a matter of fact i even had a pair of GBR spawn for the first time. however, the low pH is having an impact on the amano shrimps and pond snails in the tank. the snail's shell is brittle and paper thin while the shrimps dont look too healthy. should i opt for a kH/gH testing kit or just get crushed coral to put into the HOB filters?
