High PH, low alk

shoelaceike · Dec 31, 2015

So my PH is around 8.3-8.4 and my alk is 7.3

I'm trying to raise it to 9 but I don't want to bring my PH to undesirable levels....how can I do this.... I'm using BRS 2 part but so far only dosing alk as my calcium and mag have been stable....

I only dose a small amout at a time

Downbeach · Dec 31, 2015

What do you use to measure your pH? If a monitoring device, i.e. pinpoint, RK, etc. how old is the probe and when was the last time it was calibrated?

shoelaceike · Dec 31, 2015

I use a digital tester and haven't calibrated it in a while but I also used API and its about the same

Randy Holmes-Farley · Dec 31, 2015

pH 8.4 is not undesirably high. Raising the alk to 9 dKH with sodium carbonate spread over a couple of days won't boost pH too much.

If you strongly do not want to raise pH at all, use baking soda to boost the alkalinity. It won't raise the pH at all initially.

shoelaceike · Dec 31, 2015

Thank you....my PH is now 8.4 so I thought if I had more bicarbonate, it would raise it even more.....I'll try to figure this out....lol

Randy Holmes-Farley · Dec 31, 2015

Bicarbonate initially lowers pH a little bit.

shoelaceike · Dec 31, 2015

I meant carbinate lol....

twilliard · Dec 31, 2015

Ph is not a number I chase

Randy Holmes-Farley · Jan 1, 2016

shoelaceike said:
I meant carbinate lol....

Yes, adding carbonate raises it a bit. If added all at once, it will boost pH instantly by about 0.35 pH units for each 1.4 dKH of alkalinity, but that drops back over time as the tank pulls in CO2, and that is why I recommended spreading it out.