Fluctuating pH

[hermitmandy]

So, I've been dealing with low pH pretty much since I set my tank up last year. Initially, low meant 8.1. I switched salts from Aquaforest Probiotic to Salinity, and it's been hovering at 7.8 since. Just finished the Salinity bucket, and am now trying a small bucket of Coral Pro, as I've heard quite a bit of good about it.
Corals have mostly done well, fish never seem effected, but growth is so slow it almost seems nonexistent.
I recently got an Apex, and am now seeing this swing that goes on throughout the day.

I'd like to be able to bring my pH up to 8.1 again. I've tried buffer, opening windows, nothing has helped so far.
Alk is 10.5, calc 400, and mag about 1300.

Any suggestions on what else I could try/ do to stabilize my pH more?

 

[MagisterDamask]

You've verified the pH numbers with a test kit, right?

 

[Scorpius]

Run an airline outside to feed your protein skimmer. I tried a C02 scrubber and ran through media like crazy.

 

[MagisterDamask]

7.8 isn't bad, but it's not optimal. If it bothers you and you've tried several options without success, you could try one of these:

1. Try a reverse lighting schedule if you have a refugium (light the tank during the day and the refugium at night)

2. Run your skimmers air intake line outside, through a window or whatever.

3. Dose some kalkwasser with a dripper or your Auto Top Off. (This will only be a temporary elevation of pH)

4. Or last resort buy a CO2 scrubber and hook to your skimmers air intake. I only say last resort on this because the CO2 scrubber media does cost money. The others are fairly cheap.

 

[slim_santa_chris]

how's your refugium set up? reverse lights or 24 hour lights? what about skimmer 24 hours or reverse?

 

[Scorpius]

Unless you have a large refugium you're not going to see that large of a dent in your Ph.

 

[hermitmandy]

I have verified with a test kit multiple times. All just about spot on with the Apex.
I don't have a sump or a 'fuge(AquaClear 50 HOB on a 20G tank), though I do have some macros in the tank.

Skimmer is on 24/7 most times, only time it's off is during cleaning and occasionally after a having really bad day and not being able to stand the noise.

I'll have to see if I can find a way to run the skimmerline outside. The tank is right next to my bedroom door that goes outside, but still living with my parents poses the problem. I won't be able to drill through the wall, and my mother gets paranoid of break-ins if I do much as leave the storm door cracked, despite the screen door being locked.

 

[hermitmandy]

Would bringing the temp down a bit help at all, do you think?

Here are the rest of the current Apex readings, for reference.

 

[MagisterDamask]

How are maintaining alkalinity? Maybe you could dose your alk 2-part solution at night or drip kalkwasser at night to at least reduce the swing.

 

[hermitmandy]

How are maintaining alkalinity? Maybe you could dose your alk 2-part solution at night or drip kalkwasser at night to at least reduce the swing.

I don't dose anything except for coral foods. Everything is maintained via water change, 25% a week.

 

[MagisterDamask]

I don't dose anything except for coral foods. Everything is maintained via water change, 25% a week.

I guess if it was me, I would start with running the skimmer line outside. That seems to be the best fit for your set up right now and maybe increase the surface agitation with a power head.

Read this and do the aeration test

http://www.reefkeeping.com/issues/2004-09/rhf/

 

[MagisterDamask]

The gentleman that wrote that article is on this forum as well.

 

[Randy Holmes-Farley Verified Community Expert]

The pH is low because there is excessive CO2 in the water, which is probably from your home air.

Any way you can open windows near the tank or otherwise bring more fresh air to it?

 

[Myka]

I'd put a CO2 scrubber on the skimmer. It is more consistent than opening a window.

 

[Scorpius]

Drill a hole through a wall to the outside. lol That's what I did, but I have an understanding family.

 

[CurtnStac]

Are there any other suggestions on raising/stabilizing ph besides running your skimmer line outside? I don't have a skimmer on my 33g and having ph problems. Mine goes from 8.0 max during the day to 7.7 at night. And I do have a fuge running on reverse.
Would it be ok to just leave the ph alone if all other parameters are stable and in range (heavy lps tank)? Or does it inhibit coral growth?

 

[Ari]

I too have experienced what your concern is right now. I bought an Apex and alas, I have "real time ph" at a glance and behold, I see my pH dip in the 7.60 at night and only goes up to 8 during day. So I panic: I did big water changes 15% every other day for a week, bought a CO2 scrubber with running my skimmer line to the outside, dosed kalk, increased my Alk, reverse lighting with chaeto in the fuge, and I ended up with corals RTN, STN precious ones too. That almost made me throw in the towel. So, I just stopped monitoring for pH, removed my kalk, stopped dosing Alk. Finally my sps is bouncing back. Honestly, don't worry about pH too much, better yet, don't bother measuring it. Just look at your corals and if they seem to be doing ok, don't make any drastic change like dosing more Alk, or dripping kalk. Just focus on your Alk. Keep that one stable.

 

[dgrigor02]

Like others have said. pH lower is just a coincendence and not becuase of the salt as long as alk levels are in a reasonable range. Could be testing/calibration errors. Most likely changes in CO2 levels are to blame.

As long as pH level reach above 8 sometime during light cycle per day, I personally wouldn't worry about it.

 

[Randy Holmes-Farley Verified Community Expert]

Are there any other suggestions on raising/stabilizing ph besides running your skimmer line outside? I don't have a skimmer on my 33g and having ph problems. Mine goes from 8.0 max during the day to 7.7 at night. And I do have a fuge running on reverse.
Would it be ok to just leave the ph alone if all other parameters are stable and in range (heavy lps tank)? Or does it inhibit coral growth?

There are lots of ways to raise pH. All involve depleting CO2 in the tank (assuming alkalinity is not too low), and most of those involve using additives that consume CO2 (such as limewater for calcium and alkalinity).

If the pH is not below 7.8, I wouldn't agonize over it.

 

[UpNorthTom]

Here's my experience using outside air. I live in central Wisconsin and the weather finally warmed up last weekend so I could open a window. On Sunday morning after testing all my parameters, I decided to crack the window open an inch where I keep my 40 breeder. I've heard the fresh air would help raise my pH. I was amazed at how stable my pH became after simple opening a window and letting some outside air in. My swings in pH went down dramatically.

I dose Soda Ash at night and Calcium during the day. I keep Alkalinity at 8.5 - 9 dKH and Calcium at 420 ppm.