Water change parameters

[MarkW19]

I plan to do a 15% waterchange every 2 weeks in my 36 gallon, and was wondering how exact the water parameters have to be for the new water.

How near do temperature (78 - 80°F in the tank), pH (8.2 in the tank) and SG (SG 1.022 in the tank) have to be in the waterchange water, to that of the tank?

In particular, the pH of the new water will be higher than the tank, because it will have lowered a bit in the tank over the 2 weeks anyway. Will this pose a problem? How exact do the waterchange water parameters have to be?

Thanks

 

[jackdp]

As long as the pH isn't out of normal range (8.0-8.3) you should be fine. The tank water will be able to absorb that small of a water volume. Temperature and specific gravitly should be as close to tank water as possible, especially SG.