aqua controller

[fiorano]

for christmas i got the neptune aqua controller junior and i was noticing that the PH probe isn't very steady the numbers jump between 8.14 and 8.02 and i calibrated it and everything. but it seems to jump up higher when i add water to the sump where the electrode is. but it ussually sits at 8.02 i was just wondering how accurate this thing is and if it is very accurate i guess i gotta bring the ph up hahaha. any help would be appreciated.