Low PH?

[salty27]

Just did a water test on my already cycled tank (currently has 3 fish), and the PH reading came out a bit low (7.6) as opposed to the norm of 8.0+. Should I be concerned, and if so how can I boost it back up a bit?

 

[BlueDolphin]

I would do a water change to try and bring the pH up.

 

[jackdp]

How long has the tank been cycled? Have you been doing regular water changes since cycling? Water changes should help bring the pH up to 8.3. Also, make sure you have some surface agitation from a powerhead or likewise. Good gas exchange can help tremendously with low pH problems in some cases. Post some more info about your tank. HTH

 

[malkore]

tap water or r/o water? I've heard that tap water, due to it having buffering and hardness to start with, doesn't 'accept' the buffering changes your salt blend wants to make.
3 cups of IO salt in 6 gallons of tap water didn't give me a pH of 8.2, but the same ratios using r/o water DID get me to the right pH.

 

[ambulocetus]

Good gas exchange can help tremendously with low pH problems in some cases.

How much of a difference? I have been fighting a running battle with low pH (7.2) and my tap water is a perfect 7.0. I have aragonite in there, lots of rock (which has somewhat crumbled and dissolved in the past month!) and my pH would not rise above 7.8. Finally iused a buffer, which has maintained 8.2 for about a week now... Anyway, i do have a glass top on my 30 gal and had noticed the above advice (plus trawled through hours of the archives! )
I am not comfortable with romoving the glass top completley (small kid's toys dropped into tank, small kids trying to reach their toys from inside the tank !!!) but i would remove half of it if that would help my pH stay higher.
Thanks

 

[jackdp]

Ambulocetus....Increased gas exchange will in turn help to blow of excess carbon dioxide that may have built up in the water. The excess CO2 will drive the pH down. In your case there are three things that could help.

1. Remove all or a portion of the glass top to allow for more water to air contact.
2. Aim a powerhead towards the water surface to agitate it and facilitate some gas exchange.
3. Thirdly and a little more complicated...try to get some fresh air to the tank. Excess CO2 in your house or room will also worsen this problem. One way to check...remove a small dish of water from the tank..check the pH and then place near an open window for an hour or 2 and then check again. If the pH rises significantly then you may have low O2/High CO2 in your aquarium room. I doubt that the CO2 issue would keep your pH at 7.0 but addressing it couldn't hurt either. HTH

 

[Atari]

You could also look into the possibility of replacing your glass top with eggcrate material. That would solve the gas exchange problem and at the same time won't allow much of anything to fall in the tank.

 

[ambulocetus]

Great idea, thank you Atari. Certainly better than the buying a large canopy (and stand) and installing a small extractor fan to it! Heh he, sometimes the simple ideas slip by and we head straight to the complicated!

 

[dustybrannum]

My pH was fine for the first couple weeks then the last two have been low 7.6 range. I buffered some with no help. I have plenty of surface water movement and do 20% every week or week and a half. All my other readings are great except CA levels are only 320 and my nitrates are 0. I have been using some Mrs. Balls as kalk to replace my evaporation and the calcium levels have not risen. Could I not be using enough or could my coralline algae just be using that much of it trying to get ahold everywhere. Would hair algae lower pH or the calcium levels? I have been battling it a good bit.