Ph at 7.6...how to raise is

Bperau · Jun 13, 2017

after hooking up an apex controller last week and calibrating the ph probe I realize my ph is siting at 7.6 and my corals do not seem to open as much. Only thing I did was a 25-30 gallon water change in which I switched from Red Sea pro salt to fritz pro salt. Maybe they are just adjusting from the water change but my ph sitting that low is still kind of scaring me. I took out a cup of water and put an aerator to it for an hour and the ph remained the same as in the tank. After reading a bunch of stuff could it be I need to up my flow? It's a 125 gallon tank, alk is 10, cal is 420-440, temp is 78-79 ph is 7.6. I don't want my alk to go up so I'm not adding anything. There's a gyre 130 on one side of the tank, a jebao pp8 on the other and two 700gph return pumps (before head loss and they are older pumps)

Randy Holmes-Farley · Jun 13, 2017

IMO, a test error is still likely.

Flow is not the issue in typical reefs. Elevated CO2 in your home air is the issue.

Try the aeration tests (inside and out) in this article:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

Bperau · Jun 13, 2017

I did that when inside air. I'll try it with outside air but being 95 during the day outside my windows and doors will remain closed lol

AdamNC · Jun 13, 2017

Is it a constant 7.6 or is that just the NTL? What's it at around late afternoon? 5:00pm, 6:00pm time frame. Mine will usually dip down at night to about 7.6 and by the end of the day up to about 8.1. Don't see any issues and I run a SPS dominated tank. For a while I was needlessly chasing the numbers until I realized it's just the way my tank cycles.

Bperau · Jun 13, 2017

Only going up to 7.2 7.3 area during the day. I just added some soda ash from BRS and brought the ph up to 7.76, KH is sitting at 10 which in fine with. I'll see how long it remains at that level. Going today to grab some Chateo algae and get it in my fuge again now that I don't have phosphate remover running in the tank. Maybe the light on over the fuge at night with some Chateo will help

Randy Holmes-Farley · Jun 13, 2017

Bperau said:
I did that when inside air. I'll try it with outside air but being 95 during the day outside my windows and doors will remain closed lol

What happened inside?

Bperau · Jun 13, 2017

Ph remained the same with the inside air

Fitzreefer · Jun 13, 2017

A few things. Have you checked your pH in the recent past and what were the #s. It could be too much CO2 in the house. With that aeration test you did, you are supposed to take another cup of water outside and do the same thing to get results and compare. If the pH reads higher outside, then it could very well be a CO2 build up issue. CO2 in your tank water will be affected by the CO2 in the house air, and will lower your pH. Additional aeration with household air will most likely not fix this. If that does end up the case, either a CO2 scrubber in line to your skimmer air feed line or an outside airline running to your skimmer will be needed to reduce the CO2 in your tank water. I did the latter to correct the problem in my situation.

Bperau · Jun 13, 2017

When I get back home I'll test it outside. Where did you run a line to get outside air? Would the garage count?

Fitzreefer · Jun 13, 2017

I've heard of people going to the garage, but I guess I would be concerned with automotive fumes and other chemicals kept in the garage. There are reasons the garage is sealed off from the house.

Bperau · Jun 13, 2017

Haha my garage is used as storage. Truck doesn't even fit in it

ReeferDave01 · Jun 13, 2017

I had same exact issue. I got inside CO2 meter to test internal CO2 and it was reading 400-900 (which is normal). I was constantly getting 7.6-7.7 pH to no avail. Was unable to run line outside the house & cant leave windows/doors open (pH would go higher with them open). Only solution was CO2 scrubber. I then started running 2 dose and went from 7.8-8.0 with scrubber to 8.1-8.2 with 2 dose.

Bperau · Jun 13, 2017

Iv never heard of them. I'll have to research them

Fitzreefer · Jun 13, 2017

Looks like everybody jumped on and answered at the same time. As you can see it's been a topic of discussion. I think becoming more prevalent in newer, tighter homes.

Centerline · Jun 13, 2017

I scored a C02 meter from amazon and was surprised just how high it was in my home. Two people a small dog and a cat can create a lot of C02. The BSR C02 scrubbers work. I found that running one brought my daily average up from 7.6 ish to 7.9. You do have to make sure you keep a little water in the bottom of the reactor and change the media when it turns blue. I then added a kalk reactor that tops off about an hour before the tank ph low (around 6 am) and this brought it up to a daily average of 8.1 or so.

Bperau · Jun 13, 2017

That's what it's looking like.

Bperau · Jun 14, 2017

Did the air test with outside air and sure enough the ph shot up. I ordered some co2 absorbing media from marine depot to put in a reactor so will see how that works

Randy Holmes-Farley · Jun 14, 2017

Bperau said:
Did the air test with outside air and sure enough the ph shot up. I ordered some co2 absorbing media from marine depot to put in a reactor so will see how that works

OK, so the issue is clear. Good luck!