Ph drops significantly...what is going on? (Update)

[Jchillin]

The ph in my 30 gal tank has been dropping for over a month. The high was 7.2/7.4 since it was established several months ago. Since the beginning of April, it has been dropping slowly. This afternoon, I tested it and it's now at 6.0 (the lowest my indicator will show).

I also tested my 75 gal and it is at a steady 7.4 and has been since day one. I recently transferred my angels from the 30 gal to the 75 gal, but the ph drop began well before that.

Temp is a steady 80d and I have 0 NH3 and NO2 and 20-40ppm NO3. It's running on a foam, bio-ball filter only, also for several months.

Any ideas?

 

[krap101]

do you have a piece of driftwood or limestone?

 

[Jchillin]

Yep, small piece that has also been in the tank for several months (October 2004).

 

[Fishyfanatic]

JC- This may sound like a shot in the dark, but how large is your Apple snail? Does it look healthy, shell wise?

 

[krap101]

yeah thats a possibility... but a snail wouldnt affect the ph that much. but it culd..

 

[greenmaji]

do you have any veg. matter.. like plants that might be decomposing in the water? did you test the driftwood for a ph drop? how often do you replace your filter media? hth

 

[Fishyfanatic]

Actually Danny, I had 2 in my 10 gal tank that sent the pH so low, it was undetectable by the test kits. It has something to do with the calcium being pulled from the water for the snails shell and not being compensated by calcium additives that leaves the pH buffer shot. Again, it's a shot in the dark. This was something that I had to go through about a month ago. That's why I no longer have snails. I guess I could have just added calcium.

 

[greenmaji]

guess the question that would answer the snail question is has your KH gone down with the PH.. if so maybe baking soda or just to put a little cc in the filter to supplement the snail's needs..

 

[Jchillin]

how large is your Apple snail? Does it look healthy, shell wise?

He's huge (squash ball sized), but thank goodness, he's also healthy.

do you have any veg. matter.. like plants that might be decomposing in the water? did you test the driftwood for a ph drop? how often do you replace your filter media?

No veggie matter and no live plants. The driftwood test sounds reasonable. Could aging driftwood wreak this much havoc?

It has something to do with the calcium being pulled from the water for the snails shell and not being compensated by calcium additives that leaves the pH buffer shot.

Now that I think about it, that sounds more likely than anything else. The size of the snail in relation to the tank could deprive the water of calcium. I wish I had thought of it earlier.

I'll remove the snail and see if it changes things and post results (also combined with the driftwood test)...one or the other...no doubt.

Thanks guys!!! Kudos enroute!

 

[greenmaji]

glad to help the Mr Bill anytime!!!

 

[Fishyfanatic]

You know JC, I never would have put 2 and 2 together with the snails when my pH crashed either. Then I noticed that the huge apple snails shell was healthy and the other small one was starting to crack. The huge one was pulling all of the calcium from the tank. Since taking back the snails, my tank is very healthy with a stable pH. You may need to do several water changes before it is back to normal.

 

[Jchillin]

Fishy, you won't believe this but I had given one of these to my mother-in-law for her goldfish tank and her ph went down some weeks afterward. I was pulling my hair out because I never got to test her water, it was done by the LFS. The snail died sometime after (a long story).

But the parallel was present and I would never had figured it out.

AA is the greatest resource on the planet.

Thanks again fishy.

 

[Fishyfanatic]

No problem JC! You know, I never thought that I could actually help YOU. You seem to be always helping ME. Sometimes the stars and universe DO line up.

 

[greenmaji]

do you think a little CC in the tank or limestone could supplement the calcium in the tank water for these snails?

 

[Jchillin]

No problem JC! You know, I never thought that I could actually help YOU. You seem to be always helping ME. Sometimes the stars and universe DO line up.

Who said the door only opens one way? LOL. The best information comes from experience and to be honest, I had gotten so used to "just having" my snail that I completely forgot that the shell absorbs calcium.

do you think a little CC in the tank or limestone could supplement the calcium in the tank water for these snails?

Sure, it would work. Mathematically, it wouldn't be worth the expense and effort to do just for one overweight snail. If it were a problem with the tank itself and was needed for the entire community, then yes. And for the record, I love snails.

 

[BrianNY]

Sorry to disagree with everyone here but.........

As an aquarium ages the normal biological activity from fish, bacteria and plants will work to lower the pH. A crash will usually occur if the water has little or no buffering capacity. In order to fully understand what's occuring in your tank Bill, you need to know the KH. I'm assuming it's less then 3 dh. If this is the case you will need to add some carbonate hardness to your tank to prevent another pH crash.

 

[Jchillin]

Not that the number is any better than what you posted Brian, but the kh is 4 dh. Any suggestions? CC etc.?

Not the snail huh?

 

[greenmaji]

from what I understood a KH of greater than 3 up to 5 was a minimum for buffering the PH... if this is wrong I need to hear the answer to this one!

 

[BrianNY]

I don't think it's the snail. LOL. Recheck your KH with a new test kit. The tests are inaccurate if the reagent is old. If in fact the dh is 4, you've got plenty of buffering capacity.

How much water do you change? How often do you clean the filters? How often do you gravel vac? These are all guards against a pH drop.

 

[greenmaji]

ahh I got one.. do you gravel vac under the driftwood? stretching on this one..LOL