Chronic PH Problems

[motoman]

I have a number of tanks but a common theme in one tank, a JBJ NANO Cube is that of chronic dangerously low PH. I have approximately 10-12 lbs. of extra fine sand substrate, about 10bls. of very Live Rock covered in purple and green coraline algae. Inhabitants include two bubble tip anemones (one split to two), two small/medium clowns, one cleaner shrimp, 3 hermit crabs, 1 margarita snail, 1 astrae snail, 3 nassarius snails, 2 fighting conchs, dozens of very small brittle stars, GSP, 3 small Kenya Trees, 2 Xenia, 1 baby toad stool leather and a variety of other flora and fauna.

The Kenya Trees, anemones and Xenia are suffering from the low PH low 7s to 6s! This even with reef dissovling blocks, Reef buffer, added aragonite live sand. Nothing appears to buffer this. I change the water 20% every one to two weeks. The Toadie is near an intake in case he decides he wants to release chemicals. I change the carbon once every couple of months (about 3 cups worth). I have bio balls and bio rings in addition to the sponge filters that are rinsed in water from the tank at every other water change. Any ideas for a natural buffer solution vs. regulating with chemicals? If you need more details, please ask and I will provide any information. BTW, all added water is RO from LFS and I know others who get water from here as well with no issues but much larger tanks.

[Randy Holmes-Farley]

I don't believe that the pH is really in the 6's.

How are you measuring pH?

What is the alkalinity?

If the pH really is low, this article will help:

Solutions to pH Problems
http://www.advancedaquarist.com/issues/june2002/chem.htm

[motoman]

Measured at LFS with quick dip test strip and electronically. I did an extra water change and my Xenia are still toast today. Toadie is coming back fast as are the Kenyas and to an extent my Anemones and GSP.

[Randy Holmes-Farley]

I'd confirm the pH reading some way as I'm skeptical that it is below 7 unless you poured in a bunch of acid.

[motoman]

Thanks for your help. I was told by a few people and my LFS owner that the JBJs are notorious for high carbon dioxide and low Ph as a result. The article you sent me seems to present this as a potential issue so I may look into a surface agitator for additional oxygen transfer at the surface. I wanted to avoid the additional cost and the loss of aesthetic appeal but rather my corals and fish live than anything else.

When time and money permit, i will be getting a bigger and hopefully better set-up that should be a little more resilient to this issue.

[Randy Holmes-Farley]

I was told by a few people and my LFS owner that the JBJs are notorious for high carbon dioxide and low Ph as a result.

That could be true. If CO2 has built up, simple aeration will help. :)

[motoman]

Would you think just turbulance/agitation at the surface or would it be better to run an air line into a pump for bubbles? I used to when I first got it, have an air stone run into the sump area under the ceramic rings to keep detris from accumulating over time. I quit doing this as the bubbles popped at the surface and the salt accumulated on the lens hindering light output. I may go back to this scenario to see if it helps if you recommend it. I also thought the additional air hitting the bacteria would be a good thing kind of like a quasi, penguin filter wheel.

power head (would have to buy)? air stone (have but salt and evaporation issues)? Which would you recommend?

[motoman]

"Airline to a pump" Should be "airline into the sump" Sorry for any confusion.

[motoman]

Also, how can I measure dissolved oxygen or rather CO2 build-up? I would imagine this would need to be done at the tank as any removal of water and transfer to a testing place would yield inaccurate results.

[Randy Holmes-Farley]

CO2 is unrelated to oxygen in this context.

More agitation will help, and a good skimmer is even better.

The way to test if CO2 is the issue is to take out a cup of water and aerate it with an airstone for an hour using outside air and then a different batch with inside air. Depending on where the pH rises, it is either just the tank or the whole house that has elevated CO2.

[motoman]

Ahhh, yes I do remember reading about this test. I will do that asap. Thanks a lot for all your help.

[Randy Holmes-Farley]

You're welcome.

Let us know what you find. :)