I have a 125-gal that has been having a low pH problem for close to a year now. Have 2 pacus, 2 oscars, a shovelnose and a hibrid cat, and aquarium rocks/large rocks. I have a custom 3-compartment sump with filter media, bio-balls and dish scrubbers. Nitrite, nitrate, and ammonia have all had their problems in the past (like months ago) but are currently fine. However the pH keeps dropping. I use Alkaline buffer to raise pH, but each day it keeps dropping as much as .5 pH. I have recorded under 4pH more than once with my digital pH reader. All of my other tanks are fine (30s, 55) except this one. I recently tested my GH and KH (which I have never done). It took 17-18 drops to change color from orange to green (GH test) and took 1 drop to change from blue to yellow (KH test) - in other words it was never blue. Fish have almost completely lost appetite. I feed pellet food and the occasional red meat, but have been feeding small amounts every other day.
I was wondering what could be the issue with this tank, why the pH won't stop dropping daily and why the GH seems to be in the brackish range, while the KH is non existent. Any thoughts? Thanks in advance for taking the time to read.
I was wondering what could be the issue with this tank, why the pH won't stop dropping daily and why the GH seems to be in the brackish range, while the KH is non existent. Any thoughts? Thanks in advance for taking the time to read.