Freshwater PH/ Coral Question?

[ScottoMacD]

I read once (only once) years ago that when placing coral in a freshwater tank to buffer up the ph.

That it was possible that once the coral has aged long enough in the system that it can actually then begin to cause the opposite affect and cause the ph it suddenly drop off? Almost like it wears out it's effect. (for lack of a better term)

Someone I work with says that it is impossible. I do not doubt her explaination at all...In fact I know that she is quite knowlegable about this particular subject, But for some reason I just cannot get the article that I read completely out of my mind (must have been very convincing) when talking about this subject.

Has anyone else ever heard such a theory? I'm just curious?

Thanks.

[RTR]

I use coral rubble to buffer up water as required. I start with some amount in a nylon bag in a canister and monitor the pH/GH/KH of the tank until it is where I want/need it to be this may require adding more to the bag, or removing some. The coral rubble is coarser than most crushed coral substrates, so does not impede water flow.

After some time, the pH/GH/KH will start slipping as the coral becomes coated with biofilm and does not exchage with the water as freely. When this happens, I match the approximate quantity in a second bag, and trade them out. I rinse the first bag, allow it to dry, then re-rinse to get rid of the dead biofilm and re-dry. The original bag is then ready for the next trade-out.

If the tank is for rift lake fish or such that want to be hard and alkaline, I just use aragonite substrates. But this is not nearly as controlable as measured quantity in a filter.

HTH

Was what you read from something I wrote? - the technique is not one I devised, but is one I use if needed.

[stik6shift98]

yes putting coral in your tank will raise your ph...i have done it and it has worked

[ScottoMacD]

Originally posted by stik6shift98
yes putting coral in your tank will raise your ph...i have done it and it has worked

Thanks for the reply stik6shift98, but if you re-read my question.
I am asking about coral reverseing it's affect after a period of time.

Thanks again though.

[RTR]

And I did not fully answer that either - but the implied answer is that the elevating effect can be blocked by bacterial/infusorian overgrowth blocking solution of the coral. It serves as an attachment site just as most hard surfaces do. So trade-out or rigourous cleaning (bleach soaks and neutralization or drying and rinsing) are needed to maintain the positive effect. I opt for the less labor-intensive technique. :rolleyes: I don't know that it would host enough bacteria to actually depress water parameters as much as it just loses the ability to support them.

[ScottoMacD]

Thanks Robert.

Anyone else have 2¢ to throw in?

[stik6shift98]

oh sorry i didnt see that....and the answer to it reversing the effect is no....it cant make the ph go down....