Very low PH problem

[rdavidw]

Hey guys,

 

Back around December I was out of the country for three months and the people caring for my tank let it crash.  There was a big storm and it kicked a circuit breaker off.  Lost everything, but looking forward to starting over.  Added 

 

The tank is a 150 gallon, with a old school deep sand bed refuguim, Skimz  SM202 skimmer with a biopellet reactor running into it, chiller, dosing system, wavemakers and so on.  I used to run cheato mirco algae in the refugium but it died off when I added the bio pellets.

 

After the tank crashed, I removed as much of the funk as I could but left the rock in.  Did a few water changed and just let the skimmer run for a month.  I added a few fish and snails and started getting some decent coralline algae.  Picked up a few frags of Zoos, a Duncan, Candy Cane and a few little shrooms.  My plan is to get those test frags growing well before restocking the tank.

 

They are not growing, the Candy Cane is opening up but not growing, the Duncan started to get 5 or six buds but a few weeks ago the Duncan closed up and so did all the Zoos.  Coraline algae also all died off.  Few sails also died.

 

My temp is stable, Calcium is at 435,  dKH is at 8.6, and Magnesium is at 1,360.  Tested the PH and its only at 6.1.  I did a 50 gallon water change with 7.6 PH water and it didn't come up much.  I am also not seeing much of a swing in the PH because there is almost nothing in the tank currently processing photosynthesis.

 

I didn't think about this at the time, or when setting up my system but I have a home brewery in my unfinished area right next to my sump and skimmer.  I have two five gallon beer fermenters that are producing about 250 gallons of pure CO2 each per month, right next to my skimmer air intake.  The tank started to crash right around the time a started some new batches of beer.

 

I suspect my primary problem is very low PH due to high CO2 levels.  

 

I just ran to airline into my airtight fermenters that run from a bubble lock to outside of the house.  This should help keep the ambient air CO2 levels lower.  I also ordered a CO2 scrubber and am going to hook it up to recycle from the skimmer cup.  I don't want to draw outside air to the skimmer.

 

1. Should I remove my biopellets and grow cheato until I get my PH up?
2. Any additives I should add to the tank to get the PH up more quickly?  Should I bump up the dKH?
3. Any other steps that I should be taking to get the PH up to the 8.4 range?

 

Thanks for any ideas or suggestions!

 

Cheers, 

 

David

 

[oceanmechanic]

6.1 is incredibly low for sure, maybe a slow drip with a strong pH buffer? Removing CO2 is the only way to raise pH without also raising dKH, but you've got room to raise it a bit.
Sounds more like the primary issue is the high CO2 concentration in the same room as the tank.

This may be a bit out there but short of improving inside/outside circulation, Snake plants (S. trifasciata) and Areca Palms are incredibly efficient plants. If the CO2 levels in your room are really that high I bet those houseplants would grow like wildfire (and make a sizeable dent in the levels) with adequate care.

[rdavidw]

8 minutes ago, oceanmechanic said:

6.1 is incredibly low for sure, maybe a slow drip with a strong pH buffer? Removing CO2 is the only way to raise pH without also raising dKH, but you've got room to raise it a bit.
Sounds more like the primary issue is the high CO2 concentration in the same room as the tank.

This may be a bit out there but short of improving inside/outside circulation, Snake plants (S. trifasciata) and Areca Palms are incredibly efficient plants. If the CO2 levels in your room are really that high I bet those houseplants would grow like wildfire (and make a sizeable dent in the levels) with adequate care.

Agree 100%.  I don't know what the CO2 concentration in the room was when the tank started to crash, but I would speculate it was very high due to the pair of beer fermenters pumping out about 500 gallons of pure CO2 into the same room.  As soon as I made the connection, I opened all the windows and turned on the brewing exhaust fan.  I am now running a airline tube from the fermenters to the outside, so they are not adding much CO2 into the room, that should help.

 

For the dKH, I am currently dosing 45ml per day of BRS Sodium Bicarbonate mix and am at a 8.6.  Should I bump that up to, maybe 60ml per day until the PH comes up a bit? Thanks for the help! 

[DaJMasta]

While you may be right that pH is causing some amount of issues, I think you need to check your pH test kit/probe and verify that it's reading out sane numbers, because I really, really doubt your tank is running acidic.  Your rocks (shells, coral skeletons, etc.) would literally be continuously dissolving in a pH of 6.1, and it feels like with that (normal) level of mineral content in the water, nothing short of complete CO2 saturation would get a pH that low.

 

For other ways to raise it, you could try switching to soda ash instead of bicarbonate as it should have more effect on pH, but you could also consider supplementing with some kalkwasser dosed daily (increases calcium and alkalinity somewhat, but has a bigger impact on pH than other supplements.)  Running an air line into the skimmer can help, the step beyond that would be CO2 absorbing media on the intake of it.

[rdavidw]

19 minutes ago, DaJMasta said:

While you may be right that pH is causing some amount of issues, I think you need to check your pH test kit/probe and verify that it's reading out sane numbers, because I really, really doubt your tank is running acidic.  Your rocks (shells, coral skeletons, etc.) would literally be continuously dissolving in a pH of 6.1, and it feels like with that (normal) level of mineral content in the water, nothing short of complete CO2 saturation would get a pH that low.

 

For other ways to raise it, you could try switching to soda ash instead of bicarbonate as it should have more effect on pH, but you could also consider supplementing with some kalkwasser dosed daily (increases calcium and alkalinity somewhat, but has a bigger impact on pH than other supplements.)  Running an air line into the skimmer can help, the step beyond that would be CO2 absorbing media on the intake of it.

Good thinking DaMasta.  I have a Hanna PHep that I calibrate about once a week for brewing.  I have also tested against cheap strips.    

 

I just stuck the tester in again and got 6.29.  I held the prob in the refugium, right where the skimmer dumps out.  I then stuck the tester in the main tank and got a 7.55.  My tank is in a basement bar.  The brewery is a sealed unfinished room with no windows and an airtight exterior door from the bar area to not let any of the brew day heat and smell into the main house.  The beer fermenters produce about 200 to 300 gallons of pure CO2 per five gallon batch of beer and are right next to the reef tank works including the skimmer.  I have just set up a vent line from the fermenters to the outside. There was likely a massive amount of CO2 in the air in that back brewery/reef works room.  The skimmer is likely taking up much of the CO2 and the PH is spiking at the skimmer outlet. 

 

Good idea on the Kalkwasser, I will give that a try.

I have ordered a CO2 scrubber for the skimmer and will set it up to pull air from the skimmer cup.

[rdavidw]

My PH is now running about 6.8-7.1.   My CO2 scrubber is being delivered today, hopefully that will help some.

 

I erroneously added more Bicarbonate trying to get the PH up, and now my dKH is 13.2.  I just got some Soda Ash to replace my Bicarbonate dosing.  

 

Should I add any Soda Ash and get both the PH and dKH up?  I just did a 50 gal water change on my 150 gal tank, the Reef Crystals mix I tested came in at 13 dKH.

 

Should I pick up some fish only salt mix like Instant Ocean and do 100 gal water change to get the dKH down and then add Soda Ash to get the PH back up?  My RO DI water is testing about 7.2 PH.  

 

I only have a few tiny frags in the 150 gallon tank and the Coraline algae died off so there is nothing up taking much of anything.  I want to get the few test frags growing before restocking the tank.  With the PH problems, the frags are still alive but are closed up.

 

Thanks again for any suggestions.  

[DaJMasta]

I wouldn't raise the alkalinity any higher, but using the soda ash to replenish it should help more with pH than using bicarbonate as things go on.  While it should help, I think you're going to be absolutely burning through CO2 scrubber media if your ambient CO2 levels are enough to turn your water acidic in this room.  You say you've installed some ventilation, but that may really be the best bet in terms of economics - the CO2 media is not the cheapest to replace.  Also worth mentioning that drying the air before the CO2 scrubber can help - especially if the room tends to be humid.

 

I don't think the RO is measuring problematically, at least, until you add the salt to it, it should be about neutral pH (7.0).

 

I don't know what your ventilation system looks like, but something like a forced air exhaust may be a good option, as it would draw air in from other parts of the house.  It may be worth getting a CO2 monitor for the room as well, since it sounds like ambient levels may be quite high.

[rdavidw]

1 hour ago, DaJMasta said:

I wouldn't raise the alkalinity any higher, but using the soda ash to replenish it should help more with pH than using bicarbonate as things go on.  While it should help, I think you're going to be absolutely burning through CO2 scrubber media if your ambient CO2 levels are enough to turn your water acidic in this room.  You say you've installed some ventilation, but that may really be the best bet in terms of economics - the CO2 media is not the cheapest to replace.  Also worth mentioning that drying the air before the CO2 scrubber can help - especially if the room tends to be humid.

 

I don't think the RO is measuring problematically, at least, until you add the salt to it, it should be about neutral pH (7.0).

 

I don't know what your ventilation system looks like, but something like a forced air exhaust may be a good option, as it would draw air in from other parts of the house.  It may be worth getting a CO2 monitor for the room as well, since it sounds like ambient levels may be quite high.

Thanks again for your help with this DaJMasta.  

 

Yes - I have had this reef tank running for about 35 years now.  Moved to a new house a few years ago and made a workshop that houses both the reef tank mechanical systems and a home brewery.  The workshop is airtight with no windows to keep the reef tank and beer making smells and humidity out of the main house.

 

I typically make a new batch of beer once every three months.  I took a year off and then just made five new batches in the last two months.  During the brew day, I run a big exhaust fan to outside the house and not much CO2 is made on brew day, compared to the fermenting process.  Each batch of beer expels about 300 gallons of pure CO2 over the two week or so fermentation period.  CO2 is about 1.5 time the weight of air so it drops to the floor, where my skimmer is.  I don't regularly test my reef tank PH but did after I noticed the tank was stressed out and my other water parameters looked OK.  I would speculate that about 40 gallons of pure CO2 per day (on top of regular household CO2) was being absorbed by the 150 gallon reef tank.  The reef tank started going south right after I started brewing more.

 

After I made the connection with the very high air CO2 levels, I modified my beer fermenters to vent from the air locks to the outside of the house.   I also ran the exhaust fan for two days and left the workshop door open and some windows near the bar with the reef tank open.  I also set up some hydroponic plants in the workshop.  Moving forward, my air CO2 levels should be much lower.  I installed my CO2 scrubber to recycle air from the top of the skimmer so that may help the media last a little longer also. 

 

Could my reef water be still super saturated with CO2?  If so, will the scrubber help pull CO2 out of the water, or will it just help prevent more CO2 from entering the water?   

DaJMasta - I like the idea of only using the soda ash to replenish the bicarbonate, but my question is how much will the bicarbonate be depleted in a tank with almost no coral or coraline algae?  Would a 100 gallon water change with fish only salt mix help remove the CO2 in the reef water and bring the dHK levels down?  I would like to get the PH levels up fairly quickly, but it looks like the levels are already starting to rise a little and the little test corals are starting to open up a little.  Maybe slow and steady is best here.

 

Cheers!

 

David

 

 

 

 

[DaJMasta]

You mentioned that the display was faring better than the sump in terms of pH, and I think that's an indicator that the issue is CO2 exposure in the sump, specifically, and either with photosynthesis or gas exchange, its being driven off reasonably where it matters more.  You may even be able to see a pH gradient in your sump - probably highest at the drain from the tank and lowest at the return point or after the skimmer.

 

I don't think your system will consume a lot of alkalinity, especially in its current state, but hopefully with some increased pH you'll get some coralline back, that and the corals should consume a little (though maybe not a lot.)  The alkalinity in the water has some amount of buffering capability, but while adding more can increase that, I don't think going over 13 dKH really makes sense in many cases - it's already on the high side generally run by stony-coral filled systems.

 

Since CO2 sinks, I wonder if an option would be to mount the intake to the skimmer and/or the CO2 scrubber for it high up in the room, just to reduce the concentration where its drawing its input from.  While I'm hesitant to recommend it given the value of gas exchange, you could even consider covering a portion of the sump if you made sure to keep the skimmer with its higher air intake operating basically all the time.  Another option would be to use an air bubbler and locate the pump somewhere outside the room, basically just forcing some less CO2 saturated air from somewhere else directly into the water.  Yet another option could be some kind of refugium or algae scrubber in the sump, especially if it was continuously lit or lit on the reverse of your tank's photoperiod.  While I wouldn't expect a massive amount of CO2 removal, you'll get some and some increase in pH, and it's a reasonable way to remove nutrients from a system.

 

It's also worth mentioning that it is normal for pH to fluctuate over the day, generally highest at the peak of photosynthetic activity and lowest towards the end of the night, when it's been the longest since it was happening - make sure your measurements are consistent in terms of when they are taken, or you could be seeing somewhat different results just based on the natural cycle in the tank.

 

The short answer to whether it's still saturated with CO2 is yes - if the pH is low, it's unlikely to be something else.  But if it's only low in the sump and not so much in the display, there may be a reasonable amount of it being outgassed into the room the display is in by the flow in the system.

[rdavidw]

14 minutes ago, DaJMasta said:

You mentioned that the display was faring better than the sump in terms of pH, and I think that's an indicator that the issue is CO2 exposure in the sump, specifically, and either with photosynthesis or gas exchange, its being driven off reasonably where it matters more.  You may even be able to see a pH gradient in your sump - probably highest at the drain from the tank and lowest at the return point or after the skimmer.

 

I don't think your system will consume a lot of alkalinity, especially in its current state, but hopefully with some increased pH you'll get some coralline back, that and the corals should consume a little (though maybe not a lot.)  The alkalinity in the water has some amount of buffering capability, but while adding more can increase that, I don't think going over 13 dKH really makes sense in many cases - it's already on the high side generally run by stony-coral filled systems.

 

Since CO2 sinks, I wonder if an option would be to mount the intake to the skimmer and/or the CO2 scrubber for it high up in the room, just to reduce the concentration where its drawing its input from.  While I'm hesitant to recommend it given the value of gas exchange, you could even consider covering a portion of the sump if you made sure to keep the skimmer with its higher air intake operating basically all the time.  Another option would be to use an air bubbler and locate the pump somewhere outside the room, basically just forcing some less CO2 saturated air from somewhere else directly into the water.  Yet another option could be some kind of refugium or algae scrubber in the sump, especially if it was continuously lit or lit on the reverse of your tank's photoperiod.  While I wouldn't expect a massive amount of CO2 removal, you'll get some and some increase in pH, and it's a reasonable way to remove nutrients from a system.

 

It's also worth mentioning that it is normal for pH to fluctuate over the day, generally highest at the peak of photosynthetic activity and lowest towards the end of the night, when it's been the longest since it was happening - make sure your measurements are consistent in terms of when they are taken, or you could be seeing somewhat different results just based on the natural cycle in the tank.

 

The short answer to whether it's still saturated with CO2 is yes - if the pH is low, it's unlikely to be something else.  But if it's only low in the sump and not so much in the display, there may be a reasonable amount of it being outgassed into the room the display is in by the flow in the system.

Ok - good plan.  I will work on keeping the workshop as CO2 free as I can and hope the reef water off gasses much of the CO2 and the PH comes down to the point where the coralline comes back.  Hopefully the new CO2 scrubber helps speed up that process.  Thanks again for the help.  

[rdavidw]

I hooked up the new CO2 scrubber on a closed loop from the skimmer lid.  After running it for about two hours the PH is already up to 8.03.  I was hitting about 7.01 before I hooked it up, with both readings taken near the skimmer outlet in the refugium.  

Edited Tuesday at 11:50 PM by rdavidw

[DaJMasta]

It is worth checking the pH at least daily to give you an idea of when the media is exhausted.  You may find that it works great but not for as long as one may like, so maybe adding a smaller (adjustable) hole in the line between the scrubber and skimmer and taking in ambient air as well, that portion bypassing the scrubber, could slow the rate of media consumption and still give you a bit of a pH boost.

[rdavidw]

10 hours ago, DaJMasta said:

It is worth checking the pH at least daily to give you an idea of when the media is exhausted.  You may find that it works great but not for as long as one may like, so maybe adding a smaller (adjustable) hole in the line between the scrubber and skimmer and taking in ambient air as well, that portion bypassing the scrubber, could slow the rate of media consumption and still give you a bit of a pH boost.

I am already at 8.34 PH!  Crazy how fast the scrubber worked.  I may get a PH controller wired to a valve on a tee after the CO2 scrubber to lock in the PH at whatever level I want.  I will see where things settle after a few days and go from there. 

 

Should be about $200 to set up:

Milwaukee Instruments MC122US pH Controller

Normally Closed 110VAC-230VAC Motorized Ball Valve,3/8" Stainless steel