pH question

[severum mama]

Hey folks, I'm having some pH issues in my 2.5 gallon pico reef. When I started the tank the pH was up at 8.2-8.3. Since then it has dropped and is holding steady at 7.8. I thought that going open-top would facilitate more gas exchange and cause the pH to rise again, but it hasn't. I've done a 40% water change since adding the new light, and even that didn't change the pH. I've been advised by some people to start using a buffer, but I don't want to mess with that as I would like to avoid pH swings. I guess my question is, is it better to have a stable pH that is low (as in FW tanks), or should I take my chances with a buffer? :?

TIA

 

[tecwzrd]

7.8 isn't anything to be concerned with and the tanks newer if I remember. IME tanks take a couple of months for the PH to stabilize.

What are your alk/ca levels at? What kind of water movement do you have?

 

[severum mama]

Ok, thanks. I don't know the alk/ca levels- I don't have a test kit for those. And yes, the tank is newer. It's 2.5 gallons, and the only water movement is an Aquaclear mini (100 gph) full of LR rubble. I assumed that the AC would be enough, hopefully I am right. It seems pretty strong for such a small tank.

 

[tecwzrd]

Filter should be fine. PH is affected by alk mostly which most PH additives consist of and and wouldn't add any alk buffer without knowing the current alk level.

Couple of good articles regarding chemicals:

Reef Aquarium Water Parameters
Low pH: Causes and Cures
A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH

 

[roka64]

I agree, that is not too low. Stability is key. You tank just finished it's cycle a so it will take time to stabalize, as Micah stated.

 

[melosu58]

Stability is key.

 

[severum mama]

Thanks again for the help! You guys rock.

I know that for FW tanks it is generally preferable to have your pH be less than ideal, but stable. I just didn't know whether it worked quite the same way for SW. I'm actually really glad to hear you all say that because I would be nervous about using a buffer in such a small tank- seems like things could quickly get out of whack.

I test the water at least every other day and the pH is consistently at 7.8, possibly 7.9. The color chart is hard to read IMO. I will keep an eye on it for sure.

 

[roka64]

I tried the buffer when I had the lid on my tank and it didn't seem to stay stable. Definitely test it around the same time each day, as it swings a little between lights off/on (lower in the AM, higher in the PM).

 

[MT79]

I would be nervous about using a buffer in such a small tank- seems like things could quickly get out of whack.

You are correct. Alk buffers only raise PH temporarily. They should be used primarily to raise Alk. The PH rise is a side effect that could come in handy, but is not a means to maintain higher PH levels. Unless you have stoney corals and/or a very high bio-load to use the Alk, it will eventually climb too high possibly causing many issues from coral death to precipitation. Proper Alk levels, a mature tank, good gas exchange(no covers, good surface agitation, etc.) and good tank turnover create good PH.

I will keep an eye on it for sure.

PH is highest just before lights out and lowest right before lights on. It would be nice to see it at atleast 8 right before lights out, otherwise it may be getting a little too low at night..

 

[severum mama]

Yes, I had heard that. I generally do my testing around 6:30-7 PM each time. I'll try doing the pH test right before lights out and see what happens. And now you've got me curious about what's going on in there are night. I stay up super late on the weekends so I think I'll bust out the test kit in the middle of the night- I know I won't be getting up early to do it.

 

[roka64]

Once your tank gets a little more mature, use a flash light with the red lense and you will be surprised at what you see!

 

[MT79]

I know I won't be getting up early to do it.

Amen to that

 

[Devilishturtles]

I know I won't be getting up early to do it.

Amen to that

Hilarious!

 

[severum mama]

Well, why try and fool myself LOL!!!

 

[madhatter208]

LOL..
Many say the early bird catches the worm..

I say its the 2nd mouse that gets the cheese