Large drop in pH

[Reef of Fillory]

Hi R2R

I had my windows/doors open the last week or so due to the moderate temperatures, and I enjoyed a couple of weeks of higher pH.

I run a nano tank [Evo 13.5 gallon AIO] and don't have/run a skimmer, so I can't connect pH media to the intake.

This is my pH monitor graph from Fusion. I started running the AC on the 13th of May. The "spikes" between days are from my nightly ALK dosage.

Here are my last 2 days:

I'm getting constant Apex notifications due to the low pH [alarm @ <7.6 pH].


How harmful are these large swings? from 7.5-8.1 yesterday, and a constant <7.8 pH?

I am going to re-calibrate my prove when I get home tonight [probe was calibrated <3 weeks ago]

Thanks!

 

[Chris04]

Yes make sure your prob is correct , but don’t chase ph not worth the stress or the frustration , coral grow faster with higher ph but grow just fine with low ph and do very good at 7.8 Just my opinion

 

[RobZilla04]

How does the livestock in the system appear to be? The healthy appearance, or lack there of, can be better than any test/probe result on the market. Don't chase pH. If anything split your evening Alk dose into two doses. Morning and evening will reduce the spiking.

 

[Chris04]

How does the livestock in the system appear to be? The healthy appearance, or lack there of, can be better than any test/probe result on the market. Don't chase pH. If anything split your evening Alk dose into two doses. Morning and evening will reduce the spiking.

I have my alk and cal dose though out the day to keep my alk stable. The most important element in a reef tank is alk in my opinion

 

[Reef of Fillory]

How does the livestock in the system appear to be? The healthy appearance, or lack there of, can be better than any test/probe result on the market. Don't chase pH. If anything split your evening Alk dose into two doses. Morning and evening will reduce the spiking.

I have my ALK dosage spread out over 6 hours in the late night/early morning to attempt to keep pH higher throughout the night [Soda ash BRS 2-part]

Of course, everything looks better and fleshier with higher pH, including increased polyp extension on the SPS. Closing up my house to run AC is what's caused the pH drop [currently sitting at 7.6, 4.5 hours into the lighting cycle].

I'm thinking that i'll need to add a skimmer to the tank purely to run a CO2 scrubber, which i've ran on previous tanks successfully.

There is a clear difference between running a pH of 8.1-8.3 and 7.5-8

 

[Reef of Fillory]

I've also found many references [including the following] that low pH leads to weakened skeletons as well as lack of growth. Even still, when someone asks about pH, how to improve etc. everyone says "don't chase pH numbers" and "don't worry about it" although I anticipate as soon as BRS finishes their series on pH testing and growth, everyone will suddenly be saying "okay, maybe I should have been thinking about an increased pH".

Now of course RHF doesn't link or quote any studies/research in this response, but he generally doesn't post about things he has no clue about.


Thanks for the feedback regardless!

 

[Chris04]

Have you tried doing kalk to keep your ph up. I do it in my ATO. Works well

 

[Reef of Fillory]

Have you tried doing kalk to keep your ph up. I do it in my ATO. Works well

Tried Kalk in ATO before I bought dosers, and it was a disaster trying to keep things dialed in. I had never used kalk before, and mixed it at a very diluted ratio, but still it spiked my ALK. I think this little tank [with no top] just evaporates too much.

Now that I have the dosers and everything dialed in, I am going to have to look for another way [aside from kalk] to improve my pH.

I have a metal halide fixture coming for the tank this Friday, so the windows will likely not be open for the summer as i'll need the AC to keep the tank cooled.

Bigger tanks with sumps are so much nicer! pH problem on other tank(s) - just throw a scrubber on your skimmer!

 

[Chris04]

Only put one or two tsp for 5 gallon of rodi water. Won’t raise it up that much on the alk that way

 

[Reef of Fillory]

Only put one or two tsp for 5 gallon of rodi water. Won’t raise it up that much on the alk that way

I don't remember the actual ratio that I mixed it at, but it was ridiculously lower than the ratio on the package instructions. The problem i'd probably have with Kalk at such a low rate is that it wouldn't have a noticeable effect on pH [Didn't have the controller when I tried the kalk] and it wouldn't keep up with coral/coraline uptake.

I'm dosing 5.5-6 ml/day to my tank right now to maintain 8.5 dkh [I did not calibrate the dosers, or test their flow rates, I just adjusted time to maintain 8.5]

 

[grassy_noel]

Hey there! I have an IM Nuvo Fusion 20 gallon (similar to your system) and I've struggled with the same issue. When I have to close up the windows for the weather or when we have a lot of people over to the house my pH drops significantly. A couple things to note:

Definitely re-calibrate your probe as good practice. However, the last time I did this (seeking higher pH readings), the calibration was actually off in the other direction and the re-calibration only made me realize things were even worse than I thought. So just prepare yourself emotionally for that possibility.

I picked up a CO2 monitor from my dad (something he used to use at work). It's interesting to see how closely correlated pH and CO2 levels in the house are. After a couple days with the windows open, CO2 level in my house stabilizes around 400 ppm. At that level I'm seeing a nice pH cycle of 8.0-8.2. After my son's birthday party on Sunday followed by two days of rain where I had to close the house up, the CO2 level was just over 800 ppm and my tank's pH is down to 7.9-8.0. No real surprise here, just interesting to see how much CO2 you can build up inside with the windows closed and some people breathing. Maybe this summer I'll put some house plants in the room with my aquarium and see if they have any significant effect on CO2 levels in the air. I doubt it will.

Like you mention, I have had good results with a CO2 scrubber on my skimmer. I am using the IM Ghost Skimmer (which isn't that great...I don't think it pulls enough air) and a BRS CO2 scrubber and my swings are now generally between 7.9-8.1 rather than the 7.7-7.9 that they were before the scrubber, so that's one option. I just bought a second-hand AquaMaxx HOB skimmer, which has a much larger pump and I'm hoping it will pull a lot more air. I'll be curious to see if it improves things further.

As a second option, for a short period I was running a macroalgae reactor. It was the DIY Marine Depot kit based on an AquaMaxx HOB reactor, a strip of LEDs wrapped around it, and driven by a tiny little Sicce pump. This had a hugely beneficial effect on my pH. I only ran the reactor lights about 4-6 hours a day, but during that time my pH would rocket up to nearly 8.3. As one might imagine, I guess chaeto removes a lot of CO2 from the water while it's photosynthesizing (lights on). The only trouble is I didn't have enough nutrients in my system to keep the macroalgae from starving, so I stopped using the reactor. If you're really concerned about pH and you've got excess nutrients to burn, this might be something worth trying.

Good luck, but I agree with the general advice here. Once you've tried a few mechanical fixes (anything that reduces CO2, and thus carbonic acid, from the water), I'd just try to put it out of your mind. Best wisdom out there is that it is just not worth trying to remedy pH levels with chemical additions (buffers, stabilizers, etc.) with the exception of the Alkalinity solution that you need to add anyway.

 

[Reef of Fillory]

Hey there! I have an IM Nuvo Fusion 20 gallon (similar to your system) and I've struggled with the same issue. When I have to close up the windows for the weather or when we have a lot of people over to the house my pH drops significantly. A couple things to note:

Definitely re-calibrate your probe as good practice. However, the last time I did this (seeking higher pH readings), the calibration was actually off in the other direction and the re-calibration only made me realize things were even worse than I thought. So just prepare yourself emotionally for that possibility.

I picked up a CO2 monitor from my dad (something he used to use at work). It's interesting to see how closely correlated pH and CO2 levels in the house are. After a couple days with the windows open, CO2 level in my house stabilizes around 400 ppm. At that level I'm seeing a nice pH cycle of 8.0-8.2. After my son's birthday party on Sunday followed by two days of rain where I had to close the house up, the CO2 level was just over 800 ppm and my tank's pH is down to 7.9-8.0. No real surprise here, just interesting to see how much CO2 you can build up inside with the windows closed and some people breathing.

Like you mention, I have had good results with a CO2 scrubber on my skimmer. I am using the IM Ghost Skimmer (which isn't that great...I don't think it pulls enough air) and a BRS CO2 scrubber and my swings are now generally between 7.9-8.1 rather than the 7.7-7.9 that they were before the scrubber, so that's one option. I just bought a second-hand AquaMaxx HOB skimmer, which has a much larger pump and I'm hoping it will pull a lot more air. I'll be curious to see if it improves things further.

As a second option, for a short period I was running a macroalgae reactor. It was the DIY MarineDepot kit based on a AquaMaxx HOB reactor, a strip of LEDs wrapped around it, and driven by a tiny little Sicce pump. This had a hugely beneficial effect on my pH. I only ran the lights about 6 hours a day and during that time my pH would rocket up to nearly 8.3. As one might imagine, chaeto removes a lot of CO2 from the water while it's photosynthesizing (lights on). The only trouble is I don't have enough nutrients in my system to keep the macroalgae from starving, so I stopped using the reactor. If you're really concerned about pH this might be something worth trying.

Good luck, but I agree with the general advice here. Once you've tried a few mechanical fixes (anything that reduces CO2, and thus carbonic acid, from the water), I'd just try to put it out of your mind. Best wisdom out there is that it is just not worth trying to remedy pH levels with chemical additions (buffers, stabilizers, etc.) with the exception of the Alkalinity solution that you need to add anyway.

I run a grow light with chaeto in the bottom half of my 1st chamber on a 12 hour reverse cycle currently. My pH dropped from the 8.2 range to 7.5 closing up the doors/windows. =(

I'm looking at the aquaticlife 115 skimmer for my second chamber just to get some scrubbed air into the tank. I may drill a hole in the side of the skimmer's collection cup to let any skim back into the tank as I also already run very low nutrients [ran low nutrients (without trying) in my last tank, and had to do the same thing with the skimmer]

 

[grassy_noel]

My pH dropped from the 8.2 range to 7.5 closing up the doors/windows. =(

Bummer...sorry about that. Skimmer and scrubber might be worth a try then.

Only other thing I can think of would be to crack a window in the room the tank's in, but that's not very energy efficient. I'm surprised in Michigan that you have a constant need for A/C in the summer...I guess I would have thought it'd be cooler up there...

Might be worth considering sticking with an LED light instead of Metal Halide if that's a primary drive for the need for A/C (or tank cooling).

 

[dragon99]

Limewater should be just as easy to dose as any 2-part. Doing it via evaporation/ATO can be a bit tricky to dial in at first. But your right, if demand is low the pH boost won't be significant.

You could also look at the revised 2-part recipe that uses hydroxide:
https://www.reef2reef.com/threads/new-diy-two-part-recipes-with-higher-ph-boost.344500/

 

[Reef of Fillory]

I've decided that the Metal Halide is what I want, and i'm willing to work around using them

We get a good deal of 78-80 degree days here, and with the MH I want to make sure that I don't get too much heat. It may turn out that I can open doors/windows in my apartment, but I won't know that until I get the fixture and get it running, so i've got to plan to not have that ability

 

[Reef of Fillory]

Just an update: this is the last 24 hrs [10:00 am 5/15 to 9:45 am 5/16]

From everything i've read, this it not a "don't worry about it' range. with a 0.3 daily swing, and an average at < 7.7

Putting in an order for the crappy fluval SP2 skimmer just to provide some better aeration, although I suspect that the low pH is a result of the CO2 levels in my apartment. The air draw will be pulled through a TLF Phosban 150 reactor filled with medical grade CO2 scrubber material.

 

[RobZilla04]

Yup, some more O2 exchange should help. If you don't want to run a skimmer just run an air stone pump someplace in the sump where the bubbles wont end up in the display.

 

[Reef of Fillory]

Yup, some more O2 exchange should help. If you don't want to run a skimmer just run an air stone pump someplace in the sump where the bubbles wont end up in the display.

I am pretty sure that the CO2 levels in my apartment are so high that it might not be beneficial to have greater O2 exchange, as it may lower my pH even further. I had thought about the air stone idea, but i've never used one, and from what i've heard about using them, they make a good deal of noise, and also "make a mess".

The way that the "sump" area in the Fluval EVO works doesn't give me much confidence that i'd be able to prevent bubbles from anything making it back into the tank.

I use a DIY media rack with filter floss on top and Chemipure Elite underneath that, then the water goes diagonally to the second chamber which then flows right over to the third chamber with the pump. There isn't a good place to put a foam block or anything like that to stop bubbles, unfortunately.

This guy @120reefkeeper drilled out a bucket and put an air pump + air stone to his sump and saw a pH improvement though, so if I can find a way to deal with bubbles, that might work.

https://www.reef2reef.com/threads/low-ph-issues-make-your-own-co2-scrubber.271306/

I did order the skimmer off of Amazon, so I may be able to just run it with the air intake plumbed to my TLF reactor and call it good. I'd rather not run a skimmer, but if that's what it takes, then that's what's i'm going to do.

 

[RobZilla04]

If your intention for the skimmer is to increase O2 gas exchange, the air stone/pump is going to do the same thing. You mention doubting that increasing the gas exchange will make a difference because you are "pretty sure that the CO2 levels in your apartment are so high..." then why choose a skimmer right off the bat? Try the air stone & bucket. Better yet a small pump or power head in the sump can agitate the surface of the water improving gas exchange.

Yes if the CO2 levels are high as you presume, it won't make a diff. Just perform the simple test with the air stone, glass of tank water, and 20 minutes of your time. Aerate one glass outside, and another inside. Then test both and compare the results vs eachother & the tank water (unaerated).

 

[Reef of Fillory]

If your intention for the skimmer is to increase O2 gas exchange, the air stone/pump is going to do the same thing. You mention doubting that increasing the gas exchange will make a difference because you are "pretty sure that the CO2 levels in your apartment are so high..." then why choose a skimmer right off the bat? Try the air stone & bucket. Better yet a small pump or power head in the sump can agitate the surface of the water improving gas exchange.

Yes if the CO2 levels are high as you presume, it won't make a diff. Just perform the simple test with the air stone, glass of tank water, and 20 minutes of your time. Aerate one glass outside, and another inside. Then test both and compare the results vs eachother & the tank water (unaerated).

The only intention for the skimmer is to introduce scrubber [low CO2] air to the water to combat the high concentrations within the apartment and the current water. I have surface aggitation in my display as well as falling through my first chamber, hitting filter floss and then dropping to the Chemipure. The skimmer I bought is the Fluval skimmer made for my tank for $46 and an airstone + tubing + air pump on amazon came out to $18. I do not own miscellaneous equipment such as airstones and air pumps to test this without purchasing those things. From a few searches, many people indicate that the salt creep associated with using air stones can be significant, and that in their AIO tanks, the bubbles from the stone inevitably make their way to the display.