pH off the charts!

nirvanadude007

Hello, I recently set up a new 29 gallon tank, cycled it, and stocked it with six serpae tetras and an albino Rainbow Shark.
Three days later (today) I check my pH and dH to find that my hardness is around 9 and my pH is above 8.8!

What happened? My pH was at 7.2 four days ago.
Ammonia - 0
Nitrite - 0
Nitrate - 8

jr.masterbreeder

Are you using coral sand in the tank? or any kind of shells for decor? If so theres your problem. Any kind of shell or coral will make the PH shoot up higher than ever... that PH would be good for Cichlids... (depending on the Species.) I keep my Yellow Labs in a 29 G with a PH of 8.4.

nirvanadude007

Hmm, well now it's measuring at 7.6 and they are still acting fine.
So, hmph.
I doubt keeping the top off would have lowered the pH by over an entire point.

Kim

Do you have any rocks in the tank?

iamntbatman

What test kit are you using? If it's the API liquid kit, notice that there are two pH tests - one for pH, one for high-range pH. The regular pH test has a ceiling of 7.6, so I'm thinking that possibly you used the high-range test the first time around, and the regular test the second time?

Tyyrlym

Yes, if the low range test reads 7.6 you should run the high test as well and vice versa. What kind of rocks are in the tank and what kind of substrate.

Also, be sure the bottles are well shaken and the test tubes clean before running the test. If you don't the test can go wonky on you and max out. I know mine used too until I got in the habit of shaking and rinsing.