X.M.Chen
Active Member
My tank have a low PH problem. The PH is alway at 7.70-7.85. I have try BRS CO2 thing to rise the PH. But have now result. Can any one help my how to deal with this low PH problem. Thank you.
Low PH
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redfishbluefish
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If it's real, it's coming for carbon dioxide. To reduce CO2 in your tank, run the air line from your skimmer to the outside....to draw in fresh air. In the winter, with the house closed up, you typically see lower pH from the built up CO2.
Also increase surface agitation of the water. Try a large water change, see if there is an almost immediate difference in the ph over the next couple days.
Are you running a refugium? Is it on a 24hr shed?
Are you running a refugium? Is it on a 24hr shed?
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X.M.Chen
Active Member
I have try the
BRS Color Changing Medical Grade CO2 Absorbent
But it didn't solve the problem I also try the little two fish brand. But same no good result.
redfishbluefish
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How did you use it? Did you use it on the air line to your skimmer? The one issue with CO2 absorbents is that they are consumed (saturated) fairly quickly....and now gets very expensive method of controlling CO2. A local friend tried this and it didn't even last a day before it needed to be changed.
Another consideration is using lime (kalkwasser) in your ATO. It helps raise pH by consuming CO2. However, you will need to monitor alk and calc levels.
Another consideration is using lime (kalkwasser) in your ATO. It helps raise pH by consuming CO2. However, you will need to monitor alk and calc levels.
bfsaunde
Active Member
I'm curious about how you used the CO2 media as well. I used it on my skimmer and my pH went from 7.9-8.1 to 8.2-8.4. I have to replace the media every 7-9 days. I know that all tanks are different, but I haven't heard of anyone using it not seeing an increase in pH.
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X.M.Chen
Active Member
I have connect the air tube to my skimmer.
john.m.cole3
cyclOps
what size tank/skimmer?
bfsaunde
Active Member
Air intake of Skimmer should be connected to output of CO2 scrubber. So if that is what you are saying, then that is correct. Did you notice if the media turned from white to a light purple color. The media changes color as it is exhausted. I do think we may need to know more about your tank before we can give any ideas. Maybe post your latest tests of parameters, tank volume, type of skimmer. Are you seeing any problems in the tank that you are attributing to the low pH? How are you measuring pH? If you are using a probe, have you tried calibrating it?
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X.M.Chen
Active Member
125 gallon tank with 40 gallon sump.
Skimmer are rated for 160gallon.
Parameter are below.
Sanlitlly: 1.25
Ammonia: 0
Nitrate 0
Calcium 490
Alk 9.5
Magnesium 1320
Ph 7.70-7.83
Using a apex controller. Just calibrated the ph pro yesterday.
Have very little algae problem. But not a big dea.
bfsaunde
Active Member
ok, Good information and even better that you are not having any issues like algae or lack of coral growth. All your parameters look good. I'm new to this forum and am unsure of the link posting policy. If you do a search for "don't chase pH in reef tank" you will get articles were there is a case being made to not worry about the pH if everything else is in order and you are not experiencing problems. I know that some aquarists will dose Kalk to raise pH or run a refugium on a reverse lighting schedule to prevent the night-time dips. The macro algae in the refugium will consume CO2 while the lights are off in the main display tank. Less CO2 in water should equal a higher pH. I would be hesitant on doing anything to drastic as everything seems ok except the number you are seeing for pH. Did you notice if the CO2 media turned purple after a few days? This would at least let us know if the Media was actually absorbing CO2 even if it was not resulting in a higher pH in your tank.
bfsaunde
Active Member
Here is an article on this forum:
https://www.reef2reef.com/threads/a-simple-fix-for-low-ph.270743/
Not sure if your situation allows for a line to run outside for fresh air
https://www.reef2reef.com/threads/a-simple-fix-for-low-ph.270743/
Not sure if your situation allows for a line to run outside for fresh air
ReeferDave01
Active Member
I just attached BRS Co2 scrubber and within a week I've seen rise from 7.8 to 8.0 and still slowly rising.
nervousmonkey
LPS Lover, SPS Enabler
For those using soda lime as a CO2 scrubber, one way to extend the life of the media is to add a couple tablespoons of water to the bottom of the canister, but don't get the media wet, or at least try not to. Drawing in humid air through the soda lime extends the life of it greatly. A little trick that @Lasse taught me. On my 135 with really large skimmer that draws a lot of air, I only have to change media once a month. Another useful trick is to use two canisters in line with each other. That also seems to preserve the soda lime, at least for me. Just my humble opinion.
bfsaunde
Active Member
NervousMonkey- I forgot to mention the water in the bottom of the reactor. If you read the instructions on the media from BRS, it says to include a small amount of water in the bottom of the reactor. I am thinking about rigging up something like they did in the BRS160 to bypass the reactor when the pH is already elevated- like during the day. Not sure how much one of those solenoids cost.
nervousmonkey
LPS Lover, SPS Enabler
Wow, BRS says that? Then I'm not just a weirdo, I have a factual statement! 
I think that what BRS did to bypass the reactor is cool but unnecessary. I've had pH readings of ~8.6 during the day and experienced no issues at all. I don't think that a solenoid is needed, since CO2 inhibits growth rates, except in a small fraction of corals that do not have the carbonic anhydrase enzyme that can convert alkalinity (HCO3-) into a useful carbon source for photosynthesis. Essentially, a small percentage of corals must rely on CO2 as a carbon source in order to photosynthesize, and there is enough CO2 in the water for those corals. IMO, CO2 is a toxin for our tanks; it inhibits growth rates and helps nuisance algae, so I scrub it out vigorously.
For those wishing to save money on soda lime, try Med Vet International. They have 3 pound bags for about $9, and prefilled canisters for around $10. I use the BRS canister with soda lime from Med Vet and it works wonderfully.
There are some skimmers that don't pull air like a typical venturi, and those do not work very well for CO2 scrubbers; one on of my tanks, a nano jbj 45, I use a Tunze skimmer that used some jet air nozzle and hence doesn't pull a lot of air through the skimmer, so my pH did not rise above 7.8 -7.9. To compensate, I added an air pump to push air through the CO2 scrubber canister into the skimmer and that helped raise pH to a better level, 8.1 to 8.2.
I also believe that pH is highly important to a tank. Chasing pH by adding buffers and chemicals will generally cause problems as people are simpy fixing a temporary problem. Good levels of alkalinity and lack of CO2, or excess CO2, are all that is needed to have good pH....
I think that what BRS did to bypass the reactor is cool but unnecessary. I've had pH readings of ~8.6 during the day and experienced no issues at all. I don't think that a solenoid is needed, since CO2 inhibits growth rates, except in a small fraction of corals that do not have the carbonic anhydrase enzyme that can convert alkalinity (HCO3-) into a useful carbon source for photosynthesis. Essentially, a small percentage of corals must rely on CO2 as a carbon source in order to photosynthesize, and there is enough CO2 in the water for those corals. IMO, CO2 is a toxin for our tanks; it inhibits growth rates and helps nuisance algae, so I scrub it out vigorously.
For those wishing to save money on soda lime, try Med Vet International. They have 3 pound bags for about $9, and prefilled canisters for around $10. I use the BRS canister with soda lime from Med Vet and it works wonderfully.
There are some skimmers that don't pull air like a typical venturi, and those do not work very well for CO2 scrubbers; one on of my tanks, a nano jbj 45, I use a Tunze skimmer that used some jet air nozzle and hence doesn't pull a lot of air through the skimmer, so my pH did not rise above 7.8 -7.9. To compensate, I added an air pump to push air through the CO2 scrubber canister into the skimmer and that helped raise pH to a better level, 8.1 to 8.2.
I also believe that pH is highly important to a tank. Chasing pH by adding buffers and chemicals will generally cause problems as people are simpy fixing a temporary problem. Good levels of alkalinity and lack of CO2, or excess CO2, are all that is needed to have good pH....
