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pH too high, nothing working

Nov 1, 2006
the pH in my tank is at 8.8 and nothing seems to be working. ive done two water changes, tried Proper pH 8.2 several times and also something similar but a different brand. it wont budge! none of the chem. stuff is expired, nor is the pH powder. ive checked it with 3 test kits. ahh!
I am also having this problem! I have a 120ish gallon system and my pH is about 6.6-6.8. I was told by the people we bought the system from to use "pH Down" but I'm wondering if there is a better way? (My Instant Ocean is measuring at a pH of about 6.6-6.8 so water change isnt going to help either...why is it so high???)
What kinds of animals are in the tank and how are they doing?

Whatever you do, I would stop using anything to adjust the pH because they don't work in the long term. If you really have a pH problem, you need to find the cause and fix that.

O2 is often an issues with pH. Are your tanks closed or open?
Norge: I hope you don't mind me participating in this thread with my pH problem. If you do, let me know.
I have 7 Euprymna Scolopes squid (one is pretty small, the rest are adults) and the system is about 130 gallons. Does low O2 make the pH higher?
Not so much O2 but the minute amount of CO2 in the air. CO2 combines with water to form carbonic acid (this is why rainwater is naturally slightly acidic and why the great cathedrals are slowly melting). Adding a protein skimmer if you don't already have one will help gas exchange.

What do you have for plants in the tank? Plants consume CO2, so if you have a big hunk of chaeto you might consider removing it or switching it to a shorter photoperiod.

pH is still too high, there arent any plants, theres 1 damsel in it and 50lbs of live rock. i have a protien skimmer.. argh im going nuts. my teacher messed up the tank a while back by using baking soda (lowers pH in freshwater tanks) and someone suggested that it might have gotten into the live rock and is now leaching out. could that be the cause? if so, should i just get rid of all the rock and replace it? we did a 100% water change after the baking soda incident.
What test kit are you using?
Most pH problems aren't really problems but poor testing.

Also, the most important thing, are you experiencing any problems with your livestock that lead you to believe you have a water quality issue?
A note on pH

I've done a lot of reading on Reef Central and elsewhere concerning pH measurement. I guess we have no guarantee of getting accurate pH measurement unless we buy a true scientific instrument, which is quite expensife. I have two Pinpoint pH monitors that give different readings of the same water, despite just being calibrated and having new sensors.

Different brands of salt mixes are manufactured to come out with different pHs. I used Kent at one time, found the pH very low and variable. I've switched to Tropic Marin and found the pH comes out about right.

Calibration fluid for meters has to be new is also not always accurate.

Generally, the consensus is that pH meters are more accurate than test strips.

One good thing - if you aim for a pH of 8.2, you have some latitude - the pH can be a bit higher or lower and still be acceptable.

Thales is right - watch your livestock carefully - if its doing well, your pH is OK.

the ph is 8.2 when i put it in for a water change. the only thing in the tank is liverock and the two tests im using are Aquarium Pharmaceuticals pH kit and Quick Dip test strips. it still isnt right...
I wouldn't trust either of those kits with a 10 foot tentacle. :smile:

If you are worried about your pH because of the numbers, I wouldn't worry. Beware of chasing numbers, its the path to leaving the hobby early both from frustration at not getting the right numbers, but also from the damage you do to your animals by trying to change the numbers.

Try this: get a cup of tank water. Test it. Then, bubble water through it with an airstone for 10 minutes. Test it again and see if there is a difference. Again though, with those test kits I wouldn't trust the readings at all. I would switch to Elos or Salifert.
ok, i'll try and find those tonight. i had two damsels in there just to see how they would do, i acclimated them properly and everything, and the next day one was dead and the other sickly. aghh. its gone down today though, around 8.3ish? im going by numbers because i want to get it right before i get the octopus. the octo the teacher got two months ago died after 3 days b/c of alkalinity (retard added baking soda).
There are about a million things that could have caused the fish to die - what has led you to believe that it was the pH?
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