Odd TA and pH problem

[aaparkr]

After getting a protein skimmer, a sulfur denitrifier, a phosban reactor and a kalkwasser reactor on my 75 gallon box of 'ocean' I thought I was set - and everything seemed to be good for a while (which is why I stopped asking those dumb questions.

Well I'm back. I am using a AquaController junior and it says my pH is 9+. It slowly crept up to there over about 6 months. Problem is my TA is under 6 dKH - measured with a new Salifert test kit. I have tried to get the TA up and I can if I add kalkwasser to the K-reactor and/or buffers directly to the tank, but then my pH gets even higher.

I bought a new pH sensor about 8 or 9 months ago and after I calibrated it, I got the same readings. The only thing I haven't done is replaced my calibration media, but I store the 2 solutions in separate sealed jars that I keep in a dark place. After reading this, I believe I will get some new test solutions even though the old ones are less than a year old.

Any suggestions or (even better) easy solutions come to mind? Would you just ignore the pH and focus on getting the TA up, or just sell the livestock and tank and start over?

There are some old pictures of of the tank at aaparker.net. It tested the same when those pictures were taken.

Tony

 

[chaderic26]

I would check out the sulpher denitrator to make sure it's working correctly. It is kind of odd. When I used Kalk I never had a algae problem. I think do to the high ph precipitating phosphates.

I would also do a series of water changes.

 

[happysak]

Tony, hi there

How much water is going through K-reactor a day? PH 9 is pretty high. You can drop it by adding some vinegar or CO2 to aquarium water(monitor PH while you are doing this). What size water change you do and how often? Did you test for calcium? Take water to Leigh Anne and ask her to test for you( see if results will be same). Do not ignore high PH and do not sell livestock

Get PH down first then worry about alk.

 

[happysak]

i would also do a series of water changes.

+1

 

[aaparkr]

I change 6 gallons of water every week. I would say about 7 gallons go through the reactor in a week as that connected to my refill system. I just remembered this, the denitrifier has a tendency to lower pH because it gives off nitrogen and CO2. I was initially troubled with low pH until I routed my denitrifier output into an area of the sump with a lot of turbulence. I could probably reroute that output and get the pH lower, but that seems like a patch, not a fix.
I recently discovered that I had a problem with my return pushing more water back into the tank than the overflow was dropping into the sump (Its never done that before - years of worry free operation). I have a valve to restrict the return, so I have started using that. Because of the higher return rate, the level in the tank was higher and the sump was lower. My refill reads the sump, so I was getting more (kalk) water and I don't know how long that has been going on - months at least, so adjusting the return may help. I am surprised that no one suspects my pH reading. That is what I was expecting. Funny, I never check the pH in my makeup water. I originally got the kalkwasser reactor to give me a higher pH and TA and it did that for years. Lastly, everything in the tank looks pretty good. I have more growth than I have ever had, so I am going to get some water to Leigh Anne and see what might really be going on. Thanks everybody.

Tony