hi ive just started planted tank and brought all the stuff(wife not happy) my problem is, i set up pressurized jbl proflora with jbl test set,had it running at kh4-6 ok. changed defuser to rhinox 5000,reading showed yellow. now i cant get a consistant reading.the bubbles are a mix of very fine and course could this be the problem. ive read somewhere how to clean the defuser but cant remember wear. tank rio 240 ro water 6kh ph7-7.5 filter outlet on the left jbl test on the right,flow good,watch the bubbles go full circle. only lightly planted until next week. can anyone help. many thanks paul.