low pH

[beano]

I have a chronically low pH. i tested my source water and its about 8.0

should i be buffering my make up water? or my top-off water? or just buffer the tank as necessary?

LFS told me check pH once a month, but if am doing 10% weekly water changes with 8.0 make up water, wont that drag me down over a month?

also how quickly can i raise pH without stressing anybody in my tank: fish, lps, softies

 

[yote]

A couple of questions.
How long have your tank lights been on before running the PH test?
What is your alkalinity?
Dont add buffer unless your alkalinity is low.
And the PH is going to be its highest just before the lights are turned off for the night.
That being said.You need to test PH at 2 different times.Test it just as the lights come on,then again just as they turn off.That way you know how much it swinging.
Also,8.0 aint that bad.

 

[winyfrog]

I was thinking that as well.

 

[KidJ57]

+1 Yote

If you alk is low, then you should be adding the buffer to whatever you add to the tank that isn't at the PH you desire (i.e. top-off and make-up); however, the main thing you want to avoid is dramatic changes so don't add water with a PH of 9 (or something else ridiculous) to water that is 7.8 (obviously)...if nothing has died yet, it's not going to if your PH stays at 8; you just want to make sure it doesn't get worse, just slowly/slightly better

 

[dcantucson]

+1 Kid & yote

 

[Rcpilot]

Sometimes low pH is a sign of too much CO2 in the water. Not enough gas exchange. Or maybe enough gas exchange, but not enough O2 in the air? Perhaps you live in a new house and it's built very tight. No drafty windows nearby?

I increased the pH in both my tanks by simply putting a spare powerhead in the HOB refugium return section. The powerheads are set high in the water and shoot across the return section to churn the water quite vigorously.

Just that little bit of extra gas exchange brought my pH up about .3 units. I wish I could run the intake tube for my skimmer over to a window or through a wall to the outside. Getting fresh air from outside will increase the O2 levels in your tank significantly.

If your O2 levels are UP - then your CO2 levels are down. If the CO2 levels are low you'll have an easier time keeping the pH where you want it.

 

[ccCapt]

Low pH: Causes and Cures

Solving pH Problems
The following sections provide specific advice about how to go about solving a low pH problem. The advice can also be used to adjust the pH levels closer to natural values even if they are already within the "acceptable" range described above, but still not as high as desired. Before embarking on a pH altering strategy, however, here are some general concerns:
Make sure that there really is a pH problem. Many apparent problems are really measurement problems rather than tank problems. This problem seems to be especially common when the aquarist is using pH test kits, rather than electronic measurement with a pH meter, but all methods can and do go wrong, and you would not want to turn a good situation into a bad one simply because a pH meter was not properly calibrated. Consequently, be sure to verify the pH reading before acting in any but the most benign ways. Here are two articles worth reading on pH measurement to help ensure that the readings are accurate:

• Make sure that there really is a pH problem. Many apparent problems are really measurement problems rather than tank problems. This problem seems to be especially common when the aquarist is using pH test kits, rather than electronic measurement with a pH meter, but all methods can and do go wrong, and you would not want to turn a good situation into a bad one simply because a pH meter was not properly calibrated. Consequently, be sure to verify the pH reading before acting in any but the most benign ways. Here are two articles worth reading on pH measurement to help ensure that the readings are accurate:
  • Measuring pH with a Meter
  • A pH calibration or verification fluid using grocery store borax.
• Try to determine why there is a pH problem before enacting a band-aid solution. For example, if the problem is low pH due to excess carbon dioxide in the home's air, then more aeration with that same air may be of no benefit with respect to pH. Changing the root of the problem may be a much more satisfactory solution.

Causes of Low pH Problems
As described above, low pH problems are those where the pH is below about 7.8. That is, where the daily pH low drops below 7.8 for any portion of the day. Of course, if the pH reaches a low value of pH 7.9, aquarists may still want to raise it, but the need is not so immediate. Several things can commonly result in low pH, and the solution to each of them is different. Finally, there's nothing to prevent a tank from having all of these problems simultaneously!

The first step in solving a low pH problem is to determine why it exists in the first place. Some possibilities include:

1. A calcium carbonate/carbon dioxide reactor (CaCO[SIZE=-1]3[/SIZE]/CO[SIZE=-1]2[/SIZE] reactor) is in use on the aquarium.
2. The aquarium has low alkalinity.
3. The aquarium has more CO[SIZE=-1]2[/SIZE] in it than the surrounding air due to inadequate aeration. Don't be fooled into thinking that an aquarium must have adequate aeration because its water is very turbulent. Equilibrating carbon dioxide is MUCH harder than simply providing adequate oxygen. There would be NO change in the pH between day and night if equilibration of carbon dioxide were perfect. Since most aquaria have lower pH during the night, they also are demonstrating less than complete aeration.
4. The aquarium has excess CO[SIZE=-1]2[/SIZE] in it because the air in the home that it is being equilibrated with contains excess CO[SIZE=-1]2[/SIZE].
5. The aquarium is still cycling, and has excess acid being produced from the nitrogen cycle and degradation of organics to CO[SIZE=-1]2[/SIZE].

Solutions to pH Problems
Some solutions to pH problems are peculiar to each cause, and these are detailed below. There are, however, some general solutions that are frequently effective. These include using high pH additives when alkalinity is required. Limewater (kalkwasser) is the best choice in this regard, followed by the high pH two-part additives. These methods have the advantage of raising pH, but not raising alkalinity relative to calcium in an undesirable fashion.
Buffers alone are not generally a good method as they raise pH little, and result in excessive alkalinity. Unfortunately, the labels on many commercial buffers are written in ways that convince aquarists that the pH will be fine if they just add some buffer. More often than not, the pH is not improved for more than a day, and the alkalinity rises beyond desired limits.
Two other useful methods include growing macroalgae that absorb some CO[SIZE=-1]2[/SIZE] from the water as they grow (often lit on a reverse light cycle to the main tank to provide the maximum pH rise when the main tank is at its pH minimum), and aerating the water with fresh air.