Thanx for the reply Paul. I read the threads. I have mixed 2 scoops of the trace element mix into 300ml of water, I've basically followed the sears and conlin recipe. Although I have some KNO3, I have omitted it as my NO3 levels in both tanks range between 10-25mg/l due to reasonable fish load. As for PO4, I have to use resin to keep it at around 0.5mg/l.

I've started dosing the tanks everyday instead of weekly. The tanks are 260l and 300l, I've started off using 5ml daily in each tank. Fingers crossed!