pH swings and alk stability

[cristiand]

Hi all,

I'm new to the forum but not new to reefing (almost 10 years in the hobby). So I have a 25g IM Lagoon in my living room. This is also the room where we hang out in most of the day. My issue is that I can't seem to get my pH any higher than 8 sometimes 7.9 on most days. Given the small size of the tank it greatly varies based on amount of people in the house if I open windows or if we're away from home for a few days. I know about all the tricks in trying to keep windows open (winter here) or airline tubing outside to skimmer (unable to do that) but was wondering on other methods. Kalk dosing?

So currently i'm using the triton method. Have about 8-9 acros in there and some lps. Alk is around 8. My problem is that every time i have these pH swings the alk follows as the corals aren't using they loose color or get some tissue. Usually i'm able to get them back with everyday testing and adjustment of the doser. Also my growth rates are almost non existent because i'm constantly having this ups and downs with maintaining steady alk and ph levels (all other parameters are ok). Would kalk dosing help to buffer ph a bit better? maybe a bit every morning? I used to run a kalk stirrer on my old 75g dominant tank with good results but that talk was also in the basement where people weren't all the time. Anyway any ideas are greatly appreciated.

 

[Randy Holmes-Farley]

So when pH drops the alk rises from reduced demand and fixed dosing?

 

[cristiand]

So when pH drops the alk rises from reduced demand and fixed dosing?

Yes. Most of the time it’s pretty stable but depending on my work schedule the number of people in the room varies during the day so sometimes the ph can be higher or lower and that’s when I see the alk swing. Sorry when I see large pH swings I try and test and adjust accordingly but it’s almost always reactive rather than proactive.

 

[Randy Holmes-Farley]

How much does the alk rise?

 

[cristiand]

How much does the alk rise?

Sometimes 1dkh but can be as much as 2dkh over a few days then I spend a week or so getting it back up

 

[cristiand]

Sometimes 1dkh but can be as much as 2dkh over a few days then I spend a week or so getting it back up

 

[Robink]

Following... I have the same issue. I use a C02 scrubber to keep the ph between 8.1 - 8.2 +. When the media is close to being exhausted the ph drops and alk goes up. Since I have been changing the media as soon as it gets to 8.1 or just below I can maintain the alk between 8.6 and 8.9. I do monitor it daily in case I have to make any adjustments.
I figured that this was a normal relationship between alk and ph.
Fyi my tank is in the family room, which is generally where everyone hangs out when home.

 

[Randy Holmes-Farley]

Following... I have the same issue. I use a C02 scrubber to keep the ph between 8.1 - 8.2 +. When the media is close to being exhausted the ph drops and alk goes up. Since I have been changing the media as soon as it gets to 8.1 or just below I can maintain the alk between 8.6 and 8.9. I do monitor it daily in case I have to make any adjustments.
I figured that this was a normal relationship between alk and ph.
.

It is not a direct relationship, but rather the effect of the lower pH on demand.

The direct relationship would have pH decline if alk declined, but not the other way around.

The fancy alk controllers are certainly one way around this. Any chemical added to boost pH will just raise the pH range experienced daily, but might not alter the change in demand with CO2 levels in the home, unless it was somehow on a pH or alk controller.

 

[cristiand]

Just revisiting this subject as I am still battling this issue. Anyone have any thoughts on a small Kalk reactor through ATO to try and maintain higher pH and more alk stability. Tank is on the small size so might be overkill but don’t know what else to try.

 

[EmdeReef]

Just revisiting this subject as I am still battling this issue. Anyone have any thoughts on a small Kalk reactor through ATO to try and maintain higher pH and more alk stability. Tank is on the small size so might be overkill but don’t know what else to try.

You could try a CO2 scrubber if you run a skimmer. I live in a pretty airtight apt and it keeps my ph steady between 8.1-8.3. The CO2 inside goes over 1200-1300ppm.

Not sure about kalk and such a small tank, your chance for overdosing is high if your ATO fails. I’m sure people successfully do it though.

 

[cristiand]

You could try a CO2 scrubber if you run a skimmer. I live in a pretty airtight apt and it keeps my ph steady between 8.1-8.3. The CO2 inside goes over 1200-1300ppm.

Not sure about kalk and such a small tank, your chance for overdosing is high if your ATO fails. I’m sure people successfully do it though.

I was thinking about a co2 scrubber but it seems like the media needs to be replaced pretty frequently and that’s just another thing to worry about regarding maintenance. If I do run a Kalk reactor through ato I would set my apex to shut it off if ph gets to high. Had that set up on my old tank and it seemed to work. I’ve realized that nano tanks are a billion times harder to keep lol [emoji853][emoji853]

 

[EmdeReef]

I was thinking about a co2 scrubber but it seems like the media needs to be replaced pretty frequently and that’s just another thing to worry about regarding maintenance. If I do run a Kalk reactor through ato I would set my apex to shut it off if ph gets to high. Had that set up on my old tank and it seemed to work. I’ve realized that nano tanks are a billion times harder to keep lol [emoji853][emoji853]

Sounds like a good plan. As for soda lime, it is pricey but one jug from BRS lasted me since September. Just finished it. You can also get it for much less if you buy in bulk from medical supply stores or diving gear sites.

 

[vanpire]

I used the assembly it yourself Kalk reactor from Avast. Basic but good unit from Avast Marine.

I use it to dose kalk and I can not keep my pH between 8.1 and 8.25. Please note that I use an Apex to dose kalk during night hours to keep pH stable close to day time values. I also use a CaRx to supplement what the Kalk reactor does not.

I also keep have a separate ATO to add water to the my tank. I was thinking of a CO2 scubber but this is way easy and cheap in the long run. I guess it helps if you have an APEX already or just a good doser on a timer would do.

I could get the pH higher than 8.25 but I am not sure if that it would be more beneficial for coral growth or fish health.

My Alk is fairly stable at 11.5 dKh