My tank is 2 years old and I’ve never had a pH problem (at least that I knew of). My pH would typically go between 7.95 and 8.2. I’ve had an Apex since last December and that’s what it’s been at, which mostly agreed with my Salifert manual test (maybe a touch lower than Salifert said but nothing concerning at all). I recalibrated my probe in February after getting a new master unit through warranty from Neptune and while it initially was low, over a few days it came back up to the same range and stayed there. Each week, I do my water testing and test pH and compare to the probe. Here are some recent measurements:
2/28: salifert 8.2, apex 8.08
3/21: salifert 8.2, apex 8.06
4/19: salifert 8.1, apex 7.99
5/2: salifert 8.35, apex 8.28
5/25: salifert 8.05 , apex 7.92
6/21: salifert 8.2, apex 8.06
last week, I finally updated to the latest AOS. About 2 hours later my probe went haywire. I was getting constant pH notifications. It was bouncing up and down repeatedly. I got something like 70 notifications over a few hours. So once I got home, I recalibrated. And ever since then, my Apex has said my pH is quite low. It now ranges from about 7.65 to at most 7.95 (but may not even hit 7.8 on some days).
I’ve recalibrated at least 6 times now and each time I do it seems to read lower. I’ve gotten a new BRS probe (on Friday my old probe went haywire again dropping and rising erratically- as low as 7.2). The probe is no longer in line with my manual tests. Just today, salifert said 8.05, API said 8.0, and Apex said 7.67. I’ve gone back and forth w Neptune but they think my tank is just low. I’m starting to agree with them because everything I try doesn’t change anything. When I do the calibration (with pouches floated in the tank), the probe mostly measures them correctly (though if I leave the probe in the pouch longer they tend to drift downward)
Things I’ve tried:
Purchased new calibration pouches: no change
Purchased new probe: no change
Made a borax solution to test: not perfect but within .1 of expectations and it’s not like I’ve got lab grade stuff to measure with to make the solution
Recalibrated endlessly…hasn’t helped and frequent have to do it multiple times
Tested
Tank water in a bowl instead of tank in case there was some kind of interference, no difference
So after all this, I’m starting to think perhaps my test kits were just off all this time as it seems my probe is “correct” now (though yesterday tank said 7.83, I put the probe in borax solution for test, then cleaned it and put back in tank and then tank read 7.7 even though at that time of day it should trend upwards not down). The typically concept is CO2. There is a window right behind the tank. I opened it last night and left it open all night. The tank was warm so the fan kicked on and ran all night (back of fan is right in front of window and it points in the back of the biocube). There was no change in pH at all. I figured if CO2 was the issue that would have raised it at least a bit.
I have a fuge that grows hood chaeto that is lit opposite my tank lights. I hadn’t been running a skimmer so I put one in for aeration but saw no change.
I’m currently aerating some tank water with indoor air to test and then I’ll do it again with outdoor air and see if there’s an improvement but since an open window did nothing, I’m not hopeful.
my alk is good and stays close to 9. I dose both alk (7 times daily) and cal (twice daily). My pH probe is in the return chamber with the dosers and pH spikes alk when I dose and then settles back down.
The tank looks ok too. I have one zoa colony that’s seemed a bit annoyed lately but most of my corals look excellent and seem to be growing (anyone need some mystic sunset monti? It’s a weed )
So, I’m guessing I have low pH and have been wrong all this time in thinking it was good. Does this make sense to any resident experts here? Wouldn’t my tank be pretty upset at those pH levels? I likely can’t really do anything about it with my biocube but am planning a new tank and perhaps I need to plan for a CO2 scrubber.
Here’s my tank from yesterday:
2/28: salifert 8.2, apex 8.08
3/21: salifert 8.2, apex 8.06
4/19: salifert 8.1, apex 7.99
5/2: salifert 8.35, apex 8.28
5/25: salifert 8.05 , apex 7.92
6/21: salifert 8.2, apex 8.06
last week, I finally updated to the latest AOS. About 2 hours later my probe went haywire. I was getting constant pH notifications. It was bouncing up and down repeatedly. I got something like 70 notifications over a few hours. So once I got home, I recalibrated. And ever since then, my Apex has said my pH is quite low. It now ranges from about 7.65 to at most 7.95 (but may not even hit 7.8 on some days).
I’ve recalibrated at least 6 times now and each time I do it seems to read lower. I’ve gotten a new BRS probe (on Friday my old probe went haywire again dropping and rising erratically- as low as 7.2). The probe is no longer in line with my manual tests. Just today, salifert said 8.05, API said 8.0, and Apex said 7.67. I’ve gone back and forth w Neptune but they think my tank is just low. I’m starting to agree with them because everything I try doesn’t change anything. When I do the calibration (with pouches floated in the tank), the probe mostly measures them correctly (though if I leave the probe in the pouch longer they tend to drift downward)
Things I’ve tried:
Purchased new calibration pouches: no change
Purchased new probe: no change
Made a borax solution to test: not perfect but within .1 of expectations and it’s not like I’ve got lab grade stuff to measure with to make the solution
Recalibrated endlessly…hasn’t helped and frequent have to do it multiple times
Tested
Tank water in a bowl instead of tank in case there was some kind of interference, no difference
So after all this, I’m starting to think perhaps my test kits were just off all this time as it seems my probe is “correct” now (though yesterday tank said 7.83, I put the probe in borax solution for test, then cleaned it and put back in tank and then tank read 7.7 even though at that time of day it should trend upwards not down). The typically concept is CO2. There is a window right behind the tank. I opened it last night and left it open all night. The tank was warm so the fan kicked on and ran all night (back of fan is right in front of window and it points in the back of the biocube). There was no change in pH at all. I figured if CO2 was the issue that would have raised it at least a bit.
I have a fuge that grows hood chaeto that is lit opposite my tank lights. I hadn’t been running a skimmer so I put one in for aeration but saw no change.
I’m currently aerating some tank water with indoor air to test and then I’ll do it again with outdoor air and see if there’s an improvement but since an open window did nothing, I’m not hopeful.
my alk is good and stays close to 9. I dose both alk (7 times daily) and cal (twice daily). My pH probe is in the return chamber with the dosers and pH spikes alk when I dose and then settles back down.
The tank looks ok too. I have one zoa colony that’s seemed a bit annoyed lately but most of my corals look excellent and seem to be growing (anyone need some mystic sunset monti? It’s a weed )
So, I’m guessing I have low pH and have been wrong all this time in thinking it was good. Does this make sense to any resident experts here? Wouldn’t my tank be pretty upset at those pH levels? I likely can’t really do anything about it with my biocube but am planning a new tank and perhaps I need to plan for a CO2 scrubber.
Here’s my tank from yesterday:
