Low Ph problem

[J42766]

Okay, Im reaching out because Im about to throw in the towel. I'll keep this as short as I can. I recently bought a new ph probe knowing that my old one had dried out and was no good anymore, and I didn't much care because I was busy beating the ugly phase before I worried too much about my parameters. I bought a brs probe, and discovered my PH is really low. 7.8 in the afternoon, and dipping down to 7.6 and even as bad as 7.5 at night. I figured I had a bad probe. Re-calibrated (again) same thing, and just decided to buy a Neptune one. Same exact readings. And a cheap test kit says the same. 7.8 on a good day with the windows open. I bought a CO2 reactor and added it to the line on my skimmer that was already going outside (about 6' away). Didnt do much. I figured I should raise my alkalinity. I had been holding very steady at 8.5 dkh for 2 years with Red Sea blue bucket and 2 part dosing, but decided to go with Fritz redline which has an alkalinity of 10-11. Same thing. PH drops to 7.63 at night, and gets up to about 7.8 on a good day. I had been dosing 2 part (about 30ml each) for a couple years now to keep my Alk steady. I know its a bit early since I only have a handfull of small frags, but I wanted steady levels. So I decided to switch over to Kalkwasser, so it would consume my CO2 and become alkalinity. I now cannot keep my alkalinity stable at 10 DKH without manually dosing my 2 part. I'll be honest, I have no idea how much kalk to dose. Im up to 500 ml a day max saturation without vinegar, and my Alk and PH drop like a rock everyday. I also run a refugium 16 hours a day. What could possibly be eating up all my alkalinity. Like I said, I have just a handfull of frags, and a little bit of coralline algae. I cannot keep my PH up to proper range, without it falling back to 7.6 within hours. I see no signs of percipitation either. Im pretty sure I have a high CO2 level in my house, but I better learn to beat this without open windows because Iowa winters are brutal. What am I doing wrong folks?


Tank is a 112 gallon red sea XL425
PH - 7.6
Temp - 78
Salinity - 35ppt
Alkalinity - trying to stay at 10
Magnesium - 1500 PPM
Phosphate .04 PPB
Nitrate - 8 ppm

 

[BroccoliFarmer]

I am having the same problem. Without knowing more, the most likely culprit is excess Co2. I have a small office and my breathing alone when the door is shut is enough to drop my ph by 0.2. I ended up running an airpump from outside and an airstone in my overflow plus a recirculating Co2 scrubber on my skimmer. Between these, I am getting my PH up over 8. I still drop down to 7.8'ish at night..but working on that.

 

[J42766]

Most of the air/water exchange happens in the skimmer though. How is that not enough?

I am having the same problem. Without knowing more, the most likely culprit is excess Co2. I have a small office and my breathing alone when the door is shut is enough to drop my ph by 0.2. I ended up running an airpump from outside and an airstone in my overflow plus a recirculating Co2 scrubber on my skimmer. Between these, I am getting my PH up over 8. I still drop down to 7.8'ish at night..but working on that.

 

[BroccoliFarmer]

Most of the air/water exchange happens in the skimmer though. How is that not enough?

Most of the air/water exchange happens in the skimmer though. How is that not enough?

I dont know. I tried doing the airline into my skimmer and it didnt do anything..but once I put the airstone in my overflow...PH magically went up. I actually originally put a splitter so that some of the outside air went into the skimmer with the remaining in the overflow and it made a minimal difference. Once I did a dedicated CO2 scrubber and the air pump..poof.