Why is my pH doing this??

[ShanePike]

July 19, I set up a 28g Low Boy frag tank to house a bunch of zoas that I didn't want in my main tank. I used rock from two established healthy tanks, plus some new MarcoRocks Reef Saver rock. I also used enough sand from my main tank (11 months old) to barely cover the bottom of the tank. I then covered that with brand new sand to a total depth of around 1".

July 21, I moved over 28 zoa frags, most of them on their own small rocks so that there ended up being quite a bit of aged live rock in the system.

July 27, I added a tiny ruby red dragonet to help with the rampant amphipod population. (They swarm at night in my main tank, and plenty came over in the move. The long-term goal is to move him to the main tank.) I also added a bottle of copepods in case the dragonet wasn't keen on amphipods right away.

Somewhere just before or just after July 27 (I know, it's super frustrating that I can't remember) all of the zoas begin struggling to open. For two or three days, maybe half of them would eventually get there. The others wouldn't. Up until that point, they had been thriving. They looked great.

By July 30, none of them were opening at all so I moved them all back to the main tank where they're thriving again. I also noticed that all my stomatellas were dying. (My tanks also teem with stomatellas.)

On that same day, I finally got a controller set up and the pH graph since then might be a clue to what's wrong:

The pH seemed fine (if a little high) when I first got everything set up and got the pH probe calibrated, but it started climbing quickly. When it hit 8.6, I panicked and I turned off the lights.

The next morning I turned the lights on again, and pH climbed from 7.89 to 8.52 in just 6 hours and 20 minutes. At that point I cut two of the light bars from 80% to 40% and turned the third one off completely.

This tank has no corals in it. Just a tiny ruby dragonet, some live rock, live sand, mini nassarius, and a formerly healthy stomatella population that might have all died. There are also diatoms on the sand.

This tank sits in the same 11' x 14' room as two other tanks where the pH is great (after struggling with pH for a long time and eventually determining, thanks to Randy, that it was largely a CO2 problem).

Parameters:

• Ammonia: 0
• Nitrate: 9 (Sera)
• Phosphate: 0 (Hanna Phosphorus ULR)
• Alk: 7 (Sera)

I have a new pH probe on the way just so I can be as sure as possible that the measurements are accurate (as accurate as they can be with hobby equipment). However, this one calibrated without a problem with Apex's 7.00 and 10.00 calibration fluids. And once I saw pH climbing so high, a few hours after I calibrated, I put the probe in each of the calibration solutions to make sure it measured 7 and 10, and it did. I have also, once on the 30th and once on the 31st, taken water from this tank and measured it with the pH probe from my main tank. The measurement was only different by about 0.1 on the 31st. I can't remember the other one exactly, but they were both very close.

What could be causing pH to jump so high and so fast?? I feel like there's an easy answer that I just don't know.

 

[Johnd651]

That is a very normal swing. It has to do with CO2 consumption in the water causing fluctuations.

Long time ago, I used to have my skimmer air line ran outside to bring in fresh air to try and reduce this issue. Can also use bubblers, or a wave maker pointed at the top to increase air exchange.

 

[Garf]

July 19, I set up a 28g Low Boy frag tank to house a bunch of zoas that I didn't want in my main tank. I used rock from two established healthy tanks, plus some new MarcoRocks Reef Saver rock. I also used enough sand from my main tank (11 months old) to barely cover the bottom of the tank. I then covered that with brand new sand to a total depth of around 1".

July 21, I moved over 28 zoa frags, most of them on their own small rocks so that there ended up being quite a bit of aged live rock in the system.

July 27, I added a tiny ruby red dragonet to help with the rampant amphipod population. (They swarm at night in my main tank, and plenty came over in the move. The long-term goal is to move him to the main tank.) I also added a bottle of copepods in case the dragonet wasn't keen on amphipods right away.

Somewhere just before or just after July 27 (I know, it's super frustrating that I can't remember) all of the zoas begin struggling to open. For two or three days, maybe half of them would eventually get there. The others wouldn't. Up until that point, they had been thriving. They looked great.

By July 30, none of them were opening at all so I moved them all back to the main tank where they're thriving again. I also noticed that all my stomatellas were dying. (My tanks also teem with stomatellas.)

On that same day, I finally got a controller set up and the pH graph since then might be a clue to what's wrong:

The pH seemed fine (if a little high) when I first got everything set up and got the pH probe calibrated, but it started climbing quickly. When it hit 8.6, I panicked and I turned off the lights.

The next morning I turned the lights on again, and pH climbed from 7.89 to 8.52 in just 6 hours and 20 minutes. At that point I cut two of the light bars from 80% to 40% and turned the third one off completely.

This tank has no corals in it. Just a tiny ruby dragonet, some live rock, live sand, mini nassarius, and a formerly healthy stomatella population that might have all died. There are also diatoms on the sand.

This tank sits in the same 11' x 14' room as two other tanks where the pH is great (after struggling with pH for a long time and eventually determining, thanks to Randy, that it was largely a CO2 problem).

Parameters:

• Ammonia: 0
• Nitrate: 9 (Sera)
• Phosphate: 0 (Hanna Phosphorus ULR)
• Alk: 7 (Sera)

I have a new pH probe on the way just so I can be as sure as possible that the measurements are accurate (as accurate as they can be with hobby equipment). However, this one calibrated without a problem with Apex's 7.00 and 10.00 calibration fluids. And once I saw pH climbing so high, a few hours after I calibrated, I put the probe in each of the calibration solutions to make sure it measured 7 and 10, and it did. I have also, once on the 30th and once on the 31st, taken water from this tank and measured it with the pH probe from my main tank. The measurement was only different by about 0.1 on the 31st. I can't remember the other one exactly, but they were both very close.

What could be causing pH to jump so high and so fast?? I feel like there's an easy answer that I just don't know.

is the Alkalinity in the other tank also at 7? Increasing that can tame down swingyness in pH, along with the previously mentioned aggressive aeration. I'm not sure it has anything to do with the livestock issues however. Are you sure your salinity is good?

 

[ShanePike]

is the Alkalinity in the other tank also at 7? Increasing that can tame down swingyness in pH, along with the previously mentioned aggressive aeration. I'm not sure it has anything to do with the livestock issues however. Are you sure your salinity is good?

The alkalinity in both the other tanks is 8.5. I've been watching salinity closely, and it's at 1.0255 right now.

It's not the swing I'm most concerned about. It's that pH was at 8.6 and on pace to shoot way higher if I had left the lights on. Increasing the aeration of the water would, if anything, increase it even further.

pH that high wouldn't affect livestock?

 

[Garf]

Increasing the aeration of the water would, if anything, increase it even further.

Nah, at your alkalinity extra aeration will try to keep it nearer 8.25, obviously this depends on the amount of extra aeration and CO2 in the air.

 

[ShanePike]

OK, three more pieces of data.

One

I swapped pH probes between this tank and another tank in the same room. This is the pH graph from that other tank over the last few days:

That looks like normal pH to me. Am I right?

Before I swapped the probes, this normal tank was reading 7.98. When I swapped in the probe from the problem tank, pH dropped to 7.68.

Meanwhile, the problem tank was reading 8.15. When I swapped in the probe from the tank where the pH readings look accurate, the pH skyrocketed to 8.46

One tank is using Hydros, while the other is using Apex. Would that matter?

Two

My filter sock is getting very dirty within a day. The socks on my other tanks go for days without getting this dirty.

Three

The water started being cloudy about the time that the zoas started closing up. The appearance is like a mild bacterial bloom — i.e., not super milky, just a little cloudy.

 

[Randy Holmes-Farley]

Swapping probes without recalibrating will lead to inaccurate measurements. I’d recalibrate both meters and see what you get.

 

[ShanePike]

Swapping probes without recalibrating will lead to inaccurate measurements. I’d recalibrate both meters and see what you get.

I don't have any calibration fluid, but I have already swapped them back. I didn't keep them swapped for long.

At 11:08 AM ET (three hours ago), I readjusted the powerhead to create serious surface agitation. Other than flattening out at points, the trend line appears to be unchanged from before the aeration change. (The weird spike is when I had the probes swapped.)

Going to keep an eye on it and see if things level out or continue to climb.

 

[Randy Holmes-Farley]

I’d get some fluid since it sounds like you have not recently calibrated them.

 

[ShanePike]

I’d get some fluid since it sounds like you have not recently calibrated them.

I calibrated two days ago. Lots of data to go through above

I have a new pH probe on the way just so I can be as sure as possible that the measurements are accurate (as accurate as they can be with hobby equipment). However, this one calibrated without a problem with Apex's 7.00 and 10.00 calibration fluids. And once I saw pH climbing so high, a few hours after I calibrated, I put the probe in each of the calibration solutions to make sure it measured 7 and 10, and it did.

 

[Randy Holmes-Farley]

Ok, seems reasonable. :)

 

[ShanePike]

Ok, seems reasonable. :)

Let's assume the pH numbers are close.

1. Would pH of 8.6 be enough to mass kill stomatellas (but not mini nassarius apparently) and keep zoas from opening?

2. Why would pH be so high in a tank with nothing but live rock, live sand, diatoms, snails, copepods, and amphipods? And why would it climb when the lights came on? Doesn't that indicate that something is photosynthesizing?

 

[mook1178]

Your swings are normal variations. Keep your alkalinity tight and unless you have high CO2 (1200 ppm or higher) in your house that does not exhaust below 800 ppm. your pH will be fine.

I have run reef tanks for years and have never paid attention to my pH.

 

[mook1178]

Let's assume the pH numbers are close.

1. Would pH of 8.6 be enough to mass kill stomatellas (but not mini nassarius apparently) and keep zoas from opening?

2. Why would pH be so high in a tank with nothing but live rock, live sand, diatoms, snails, copepods, and amphipods? And why would it climb when the lights came on? Doesn't that indicate that something is photosynthesizing?

To point number 2 it is high because you only have photosynthesis removing CO2, nothing adding CO2 to counter balance. Low CO2 results in high pH.

To point number one, your high pH is not held long enough to actually concern biology.

 

[p1u5h13r4m24]

I’ve never had an issue when my ph was at 8.6. With that being said I don’t believe it’s possible for it to naturally climb above 8.5 without any type of additives. If you are really concerned cut your lights back an hour to stop it from peaking so high. However maybe it’s possible your ph probe is on its way out. When calibrating is it reading the calibration fluid accurately the next day after calibration?

 

[Randy Holmes-Farley]

I dont think pH 8.6 is a problem, and I’m suspicious it is not accurate for whatever reason. If it is accurate, aeration will lower it.
FWIW, diatoms photosynthesize.

 

[Troylee]

Let's assume the pH numbers are close.

1. Would pH of 8.6 be enough to mass kill stomatellas (but not mini nassarius apparently) and keep zoas from opening?

2. Why would pH be so high in a tank with nothing but live rock, live sand, diatoms, snails, copepods, and amphipods? And why would it climb when the lights came on? Doesn't that indicate that something is photosynthesizing?

To answer this no! My ph gets that high all the time and nothing has died.. my swings are pretty wild also and I don’t care lol.. I dose kalk thou.

 

[ShanePike]

I dont think pH 8.6 is a problem, and I’m suspicious it is not accurate for whatever reason. If it is accurate, aeration will lower it.
FWIW, diatoms photosynthesize.

Oh, yeah. I wouldn't be surprised to find that it isn't accurate. It's all I have to go on until the new probe gets here, though, so I'm trying to do what I can in the meantime.

Based on all the above ... if it's not a pH issue, any gut feel for what might have wiped out all my stomatellas and made all my zoas close up?

 

[Troylee]

Oh, yeah. I wouldn't be surprised to find that it isn't accurate. It's all I have to go on until the new probe gets here, though, so I'm trying to do what I can in the meantime.

Based on all the above ... if it's not a pH issue, any gut feel for what might have wiped out all my stomatellas and made all my zoas close up?

Possibly a contaminant like copper got in?

 

[ShanePike]

Possibly a contaminant like copper got in?

I guess anything is possible, but no source of contaminant comes to mind. I panicked when I remembered that I added the fish water and all, but then I remembered that he wasn't kept in copper at all.