DKH issues

[findingnemo1]

I seem to be having big issues keeping my dkh up. I have been adding buffer for the last 5 days and it goes in between 6.7 and 7.4.

I don't get it. Calcium is okay and my test kits are salifert and new so its not that. I know that running phosphate remover has an effect but i should be able to get it up and keep it up with a buffer.

Suggestions would be great.

Craig