Ph drop .2-.3 in one day, no changes to alk

[mike werner]

I scrub CO2 (at night only, automated). What you're describing really sounds like your scrubber isn't functioning properly; that's what I would definitely check first, including replacing the soda. Rise in alk will correlate with drop in pH, that's an effect not cause. Longshot might be some cause of increased CO2 in the house. As RHF mentions, neither furnace nor ac should do that, but other things can. For example, my kitchen is between the family room and dining room, and I keep 1 tank in each room. Simply boiling water and making a batch of pasta on the gas range will cause the CO2 level in the adjoining rooms to jump from around 600 baseline in my house to over 800 in less than half an hour. This is just an example, it comes back down just as quickly when I turn off the range and there is no measurable effect on either tank. But you might have a new unidentified cause of persistent increased CO2 in your house. You might consider getting a meter; there are many, I use this one.

rkpeterson,ya got me to thinking so I broke down the scrubber and low and behold the plate in the bottom that keeps the media from falling to the bottom came loose and starved the media of air flow but allowed the air to pass by to the skimmer.made the correction and the ph is steadly climbing.i sent ya like but want to say thanks again.ya never know do ya?

 

[rkpetersen]

I will check the scrubber. I called brs to find out if maybe the media could be exhausted even though it hadn't turned purple, they said no.

This is not entirely correct - The granules will turn purple indicating exhaustion, but if the scrubber is turned off for a period of time, they will turn white again, although at this point they have virtually no capacity to absorb more CO2. There's also the issue of channeling, although this is probably less of a concern here than with DI resin in an RODI system, for example. Check out this short article; it's about using soda lime in anesthesia, but many of the comments apply for our use too. Another issue I've had is that the plastic of the BRS scrubber reactor has a slight bluish tint that can make it tricky to tell where the purple ends and the white begins; I sometimes have to take the inner container out to be sure.

 

[rkpetersen]

rkpeterson,ya got me to thinking so I broke down the scrubber and low and behold the plate in the bottom that keeps the media from falling to the bottom came loose and starved the media of air flow but allowed the air to pass by to the skimmer.made the correction and the ph is steadly climbing.i sent ya like but want to say thanks again.ya never know do ya?

Hah! Excellent! Maybe OP will find something similar.

 

[BigJohnny]

This is not entirely correct - The granules will turn purple indicating exhaustion, but if the scrubber is turned off for a period of time, they will turn white again, although at this point they have virtually no capacity to absorb more CO2. There's also the issue of channeling, although this is probably less of a concern here than with DI resin in an RODI system, for example. Check out this short article; it's about using soda lime in anesthesia, but many of the comments apply for our use too. Another issue I've had is that the plastic of the BRS scrubber reactor has a slight bluish tint that can make it tricky to tell where the purple ends and the white begins; I sometimes have to take the inner container out to be sure.

So this turning back to white aspect that you mentioned got me thinking. I hooked this scrubber up several months ago for a few days and then took it offline because i was having too much precipitation. I left the canister in place (not hooked up to my skimmer but its not airtight so was exposed to air) and then simply hooked it back up to my skimmer about a week ago. Its possible that overtime the media was exhausting without changing color (or it changed color then changed back), so what I was left with might not be able to turn purple again. I assumed because the media was not purple i didn't need to change it out, and it did work very well for the past week or so.

I opened the canister this morning and while there was a little bit of purple at the bottom or top (i forget which) the rest was white. I replaced the media and it appears my pH is climbing again. I will update tomorrow, but I think that was the issue. Thanks bud!

 

[BigJohnny]

Sure enough, that was it. The media must have been exhausted. Btw, anyone know of cheaper bulk media than brs that works as well or better?

 

[mitch91175]

I think brs has been trying to find ways to regenerate it reliably but to no avail.

I wouldn’t call it regenerating it, but it put mine in a ziplock bag removed as much air as I could the just put it in the garage. After a while it turned white so I use that in my first canister for a few days until it turns purple again. I am going to repeat that cycle with fresh in the canister before the skimmer and used white in the first canister. It turns purple again so I think it may be working.

 

[BigJohnny]

I wouldn’t call it regenerating it, but it put mine in a ziplock bag removed as much air as I could the just put it in the garage. After a while it turned white so I use that in my first canister for a few days until it turns purple again. I am going to repeat that cycle with fresh in the canister before the skimmer and used white in the first canister. It turns purple again so I think it may be working.

Nah i don't think it works like that. Opposite of what I just experienced. You are using two canisters so you can't tell for sure unless it's all your running. It's not reusable though so I'm pretty sure it's not doing anything but turning purple

 

[mitch91175]

Nah i don't think it works like that. Opposite of what I just experienced. You are using two canisters so you can't tell for sure unless it's all your running. It's not reusable though so I'm pretty sure it's not doing anything but turning purple

Even if the 1st canister is the only one turning purple and the 2nd isn’t?

 

[Randy Holmes-Farley Verified Community Expert]

I think the media gets depleted unevenly ( like not as well deep inside a particle) and that is why old time anesthesiologists “recharged” in in various ways, but it is really just more effectively using the media. The same may happen by storing it for a long time sealed from air.

 

[BigJohnny]

Even if the 1st canister is the only one turning purple and the 2nd isn’t?

IMO you can't use turning purple as an indicator of it working, because exhausted media will turn back to white. I'm not sure turning purple means it's necessarily completely exhausted either though, I don't fully understand why it turns purple though so don't know for sure.

Moving forward, I'm purely using pH as the indicator for when the media is exhausted. The color has proven unreliable for me.

Try only using the old purple stuffed that turned white. It probably won't work but even if it does for a short time, that likely means it wasn't completely exhausted in the first place, imo.

 

[BigJohnny]

I think the media gets depleted unevenly ( like not as well deep inside a particle) and that is why old time anesthesiologists “recharged” in in various ways, but it is really just more effectively using the media. The same may happen by storing it for a long time sealed from air.

Do you know what makes it turn purple?

 

[Randy Holmes-Farley Verified Community Expert]

Do you know what makes it turn purple?

It is probably just a pH indicating dye.

 

[mitch91175]

As long as my pH is above 8 I am fine with it. Once it dips below 8 I know it is time to swap it out. I'll keep doing the ziplock bag process to have it turn white and put in the 1st canister. Is it recharging it, do not know for certain, but when I do put it in the first canister it is turning color again and the 2nd canister isn't turning at all until the 1st turns purple again. To me if it wasn't working, I'll definitely notice. My pH drops to 7.8 when it isn't working. At least doing this (for me) I am prolonging the time before I have to purchase more media and maximizing the spent media to its fullest.

 

[BigJohnny]

As long as my pH is above 8 I am fine with it. Once it dips below 8 I know it is time to swap it out. I'll keep doing the ziplock bag process to have it turn white and put in the 1st canister. Is it recharging it, do not know for certain, but when I do put it in the first canister it is turning color again and the 2nd canister isn't turning at all until the 1st turns purple again. To me if it wasn't working, I'll definitely notice. My pH drops to 7.8 when it isn't working. At least doing this (for me) I am prolonging the time before I have to purchase more media and maximizing the spent media to its fullest.

Only true way to test if it's working is to run it solo, you should try it.

 

[mitch91175]

Only true way to test if it's working is to run it solo, you should try it.

I will do it on my frag tank once the last batch that I just removed turn all white and report back here. Should be within the next few days or so.

 

[rkpetersen]

I left the canister in place (not hooked up to my skimmer but its not airtight so was exposed to air) and then simply hooked it back up to my skimmer about a week ago.!

Yes, exactly, I experienced the exact same thing when I stopped using it for a couple of months. The granules were white, but did very little and that was only for a short time.

Glad that solved the problem.

I use the BRS soda lime. There's probably cheaper around but I'm too lazy to look. Also, I more or less trust that they won't offer anything that might be harmful to the aquarium.

 

[mitch91175]

Yes, exactly, I experienced the exact same thing when I stopped using it for a couple of months. The granules were white, but did very little and that was only for a short time.

Glad that solved the problem.

I use the BRS soda lime. There's probably cheaper around but I'm too lazy to look. Also, I more or less trust that they won't offer anything that might be harmful to the aquarium.

Here are some sources:

http://www.shopmedvet.com/product/soda-lime-5-gallon-JOR553B
https://www.amronintl.com/wr-grace-sodasorb-carbon-dioxide-absorbents.html (This is what i use)
https://www.aaawholesalecompany.com...BU7L447hjYwSaioqooRHNAEz0FSh9jrxoCab8QAvD_BwE
https://www.divegearexpress.com/sofnolime-797-44-lb-20-kg-keg-8-12-mesh

I like buying in bulk so I do not have to worry about not having stuff (plus it is cheaper in the long run)

 

[mitch91175]

Guys I know that we do not feel that you can recharge the CO2 scrubbing media, but my pH hasn't dropped and the first canister is the only one turning purple again. Second canister has very little in it. I will still run my test once my current ziplock bag has turned all white again.

Maybe it turned purple prematurely or something, but it definitely it keeping my pH higher than the 7.8 when not running it.

 

[mitch91175]

 

[BigJohnny]

Guys I know that we do not feel that you can recharge the CO2 scrubbing media, but my pH hasn't dropped and the first canister is the only one turning purple again. Second canister has very little in it. I will still run my test once my current ziplock bag has turned all white again.

Maybe it turned purple prematurely or something, but it definitely it keeping my pH higher than the 7.8 when not running it.

I bet if you ran fresh media in both canisters your pH would be higher and you'd have to switch both out less often