PH low, Alkalinity high? I'm confused

[dansd]

My Alkalinity seems to be running around 12.5 dKH (4.46 meq/L), but at the same time, my PH keeps hovering between 7.8 and 8.0.

From what I understand, my PH should be around 8.3. I add Seachem's PH 8.3 buffer and it temporarily increases my PH, but the next day I need to redose.

Does it make sense that my PH keeps dropping while my Alkalinity is on the high side?

Background info: My tank is live rock/fish only 55 gal. Tank's been set up for about a year. The only thing that's changed recently is that I added some new live rock. It caused my ammonia to go up slightly, but it's dropping back towards zero. I do a partial 5 gal, water change each week.

 

[Anonymous]

My guess is that you've destroyed your Calcium level by overdosing a buffer to raise PH.

I think you should test your Calcium and Magnesium levels. If they are low (my guess) then you can do a series of water changes to get your ALK lower and your Ca and Mg higher.

A low PH is not really a problem but using too much buffer to raise PH will usually result in a problem. ALK (buffer) and Calcium need to be dosed in a balanced method. Raising one too high will deplete the other and cause problems.

Low PH is usually just an excess of CO2 or a sign that something in the tank is rotting and needs to be cleaned up.

Adding more waterflow, a bigger skimmer, and/or cleaning up detritus will often raise PH naturally.

 

[Sugar Magnolia]

Read through these.

http://reefkeeping.com/issues/2004-09/rhf/index.htm
http://www.advancedaquarist.com/issues/nov2002/chem.htm
http://reefkeeping.com/issues/2002-04/r ... /index.htm