Best solution to raise ph without raising alk

[ATB USA]

Hi I need the best solution to raise my ph and lower my alk

alkalinity is 16dkh tested twice with salfert

ph is 7.5 tested twice with ph monitor after recalibrated with solutions

calcium is 450 tested twice with salfert

I dosed more calcium to lower the alk I think this is the best way but still need to figure out how to bring the ph up.

Thanks

[Randy Holmes-Farley]

The best ways would be to switch to a method of alkalinity supplementation that raises pH, or to provide more aeration, possibly with fresher air.

There is no additive that raises pH and does not supply alkalinity.

How are you supplementing alkalinity now?

This article has more:

The "How To" Guide to Reef Aquarium Chemistry for Beginners, Part 3: pH
http://reefkeeping.com/issues/2007-05/rhf/index.php

[ATB USA]

Hi Randy
Glad to hear from you. Everything time I have a chemistry problem I look for your articles. I did read it in your ph article but was seeing if there is any other method. For the last 4 months I have been using two part. The ph has dropped in the last week. I was adding seachem reef buffer to raise ph and I overshot the alk. Now I added more ca to lower the alk is this right?
Thanks

[Bri Guy]

Just cause you raised the Ca does not mean that your alk will drop because of the dose! Unless you were shooting for an uncontrollable precipitation. Time or waterchange would be best to lower alk.

Use baked baking soda to add alk/buffer, baking gets rid of excess C02 within it. CO2 is lowering your pH.

To get rid of CO2, get fresh outside air to tank (skimmer line works)

Did you try the fresh air test. Take 1 cup of water from the tank, whats the pH? aerate it with air from inside the house for 1 hr, Whats the pH? now take it outside and aerate it for one more hr, whats the pH? let us know
that will give you a good idea of whats goin on with Co2 effecting your tank pH.

Good luck!

[ATB USA]

Ok ran some more tests
whole tank is at 7.70
1 cup of tank water after setting for 1 hour 7.77
1 cup of tank water after setting for 1 hour inside house and then 1 hour outside is 7.80

Thanks

[bertoni]

Did you put an airstone into the cup? If so, I suspect a measurement problem.

[ATB USA]

Sorry i did it wrong then i will redo the tests, but the temp is 11 degrees different between the inside of the house and outside right now
thanks

[ATB USA]

ok redo
whole tank 7.70
after 1 hour with airstone 7.78
another hour with airstone outside 7.85
Thanks

[bertoni]

I suspect low alkalinity or testing problems. What brand of pH buffers were used? How many points were calibrated and with what pH solutions?

[ATB USA]

The ph monitor probe was replaced about 3 months ago
I used 1 brand new bag of ph 4.01 and one of 7.01 to calibrate the probe yesterday. The probe is the only one in the sump. I was dosing two part alk and ca. I was also dosing seachem reef buffer to raise the ph. But yesterday when i tested alk it was at 16dkh. I retested, it was the same result. I think I will do a 40 gallons water change tomorrow and another 40 a couple of days later. Is there any other testing problems.
thanks

[bertoni]

I wouldn't trust the probe to be very accurate unless it's been calibrated with pH 7 and 10 solutions. I would get a second opinion on the alkalinity test kit, but it might be fine. If the animals look okay, I wouldn't do anything drastic until a second opinion on the pH result can be obtained.

[ATB USA]

Yes the the animals look ok. The polyps are all still open on my corals. I will get some new solution bags on monday recalibrate and retest. Shouldn't my ph be high since my alk is so high? So bertoni when can I bring over some water. Just joking i noticed that you aren't that far from me.

[Billybeau1]

What was the pH a month ago ?

[ATB USA]

It was around 8.12 so everything was fine. The ph just dropped recently I thought it might be because its been cold so we have all the windows closed but it didn't make any difference when I did the cup test.
Thanks

[Billybeau1]

I believe it is, in fact, a CO2 issue from what you describe.

However the drop seems a little excessive to me.

My first thought is maybe try calibrating your probe with 7 and 10 instead of 4 and 7.

For some reason, I think your pH is more like 7.9 or so right now which isnt bad.

Sometimes electrical interference can skew the readings on an electronic monitor as well.

[ATB USA]

I recalibrated with 7 and 10. The ph monitor works fine now the tank was actually at 8.21. I did some water change to take down the Alk.

Thanks for the help

[bertoni]

Okay, that sounds good!