sen5241b April 8, 2009 Share April 8, 2009 My 39G Biocube tank is 14 months old and in the last month or so the Ph has dropped from 8.2 to 7.8. Alakalinity is low too. I've read the article on why Ph drops but I cannot figure out the cause. Do older tanks get chronic low Ph problems? I added a bunch of chaeto a month or so ago and the nitrates dropped way down but I can't see this as being related. I do not have a CO2 calcium reactor. My skimmer with its wooden airstone probably puts a lot of oxygen in the water. I have been leaving the lids closed lately on the biocube hood but I did this last winter and it did not cause a Ph problem. Ph 7.8 Sg 1.021 calcium 400 ppm nitrates 0ppm phosphates 0ppm Alkalinity in the low acceptable range. Link to comment Share on other sites More sharing options...
Brian Ward April 8, 2009 Share April 8, 2009 My 39G Biocube tank is 14 months old and in the last month or so the Ph has dropped from 8.2 to 7.8. Alakalinity is low too. I've read the article on why Ph drops but I cannot figure out the cause. Do older tanks get chronic low Ph problems? I added a bunch of chaeto a month or so ago and the nitrates dropped way down but I can't see this as being related. I do not have a CO2 calcium reactor. My skimmer with its wooden airstone probably puts a lot of oxygen in the water. I have been leaving the lids closed lately on the biocube hood but I did this last winter and it did not cause a Ph problem. Ph 7.8 Sg 1.021 calcium 400 ppm nitrates 0ppm phosphates 0ppm Alkalinity in the low acceptable range. How are you measuring pH? Is this from a test kit or a pH probe? The probes need to be re-calibrated every month or so and typically go bad after a year. If it's from a test kit, has it expired? The chaeto should boost the pH because it is releasing O2 into the water and consuming CO2. Any change in number of fish or corals? What do your swings look like? Run a test just before the lights come on and just before the lights go out. Is there a difference? Do you run the light for your fuge on a reverse schedule? Link to comment Share on other sites More sharing options...
Origami April 9, 2009 Share April 9, 2009 Assuming the pH measurement is right, take a cup or two of water outside and aerate it for about 10 or 15 minutes. Compare the pH reading before and after aeration. If you see a substantial rise in pH, it's ambient CO2 (in the house) that's depressing your tank's pH and you may want to consider having your skimmer draw its air from a fresh (outside) air source. What is your alkalinity measurement anyway - what's "low acceptable"? Do you mean 2.5 meq/l? Here's a good low-pH article by RHF. http://www.reefkeeping.com/issues/2004-09/rhf/index.php Link to comment Share on other sites More sharing options...
sen5241b April 9, 2009 Author Share April 9, 2009 Assuming the pH measurement is right, take a cup or two of water outside and aerate it for about 10 or 15 minutes. Compare the pH reading before and after aeration. If you see a substantial rise in pH, it's ambient CO2 (in the house) that's depressing your tank's pH and you may want to consider having your skimmer draw its air from a fresh (outside) air source. What is your alkalinity measurement anyway - what's "low acceptable"? Do you mean 2.5 meq/l? Here's a good low-pH article by RHF. http://www.reefkeeping.com/issues/2004-09/rhf/index.php Thanks, I read that excellent article a week ago. I checked the Ph this morning before the lights came on and it was below 7.8! I'll try aerating some water and see what happens. I'm also going to try a different test kit. With this kind of thing you always ask what has changed in the tank and the only change to the system was the addition of chaeto a month ago and that should be raising the Ph? Link to comment Share on other sites More sharing options...
sen5241b April 9, 2009 Author Share April 9, 2009 Assuming the pH measurement is right, take a cup or two of water outside and aerate it for about 10 or 15 minutes. Compare the pH reading before and after aeration. If you see a substantial rise in pH, it's ambient CO2 (in the house) that's depressing your tank's pH and you may want to consider having your skimmer draw its air from a fresh (outside) air source. What is your alkalinity measurement anyway - what's "low acceptable"? Do you mean 2.5 meq/l? Here's a good low-pH article by RHF. http://www.reefkeeping.com/issues/2004-09/rhf/index.php Thanks, I read that excellent article a week ago. I checked the Ph this morning before the lights came on and it was below 7.8! I'll try aerating some water and see what happens. I'm also going to try a different test kit. With this kind of thing you always ask what has changed in the tank and the only change to the system was the addition of chaeto a month ago and that should be raising the Ph? Link to comment Share on other sites More sharing options...
lhcorals April 9, 2009 Share April 9, 2009 If your Alk. is on the low side of the scale try to bump it up a little. I had the same problem about 8 months ago. I raised my Alk to 19 dkh and now my PH is 8.1 to 8.3. Hope this helps. Link to comment Share on other sites More sharing options...
sen5241b April 9, 2009 Author Share April 9, 2009 If your Alk. is on the low side of the scale try to bump it up a little. I had the same problem about 8 months ago. I raised my Alk to 19 dkh and now my PH is 8.1 to 8.3. Hope this helps. But what causes Alk to fall and how do you boost it? I'm trying to get to the root cause. Link to comment Share on other sites More sharing options...
Origami April 9, 2009 Share April 9, 2009 Do you use a reverse light cycle on your macroalgae fuge? Have you considered doing so? This helps to balance the nighttime respiration of photosynthetic organisms, spreading out the exhaled CO2. What's your max pH (just before the lights go out)? Link to comment Share on other sites More sharing options...
sen5241b April 10, 2009 Author Share April 10, 2009 Do you use a reverse light cycle on your macroalgae fuge? Have you considered doing so? This helps to balance the nighttime respiration of photosynthetic organisms, spreading out the exhaled CO2. What's your max pH (just before the lights go out)? Yeah, I have the reverse light schedule for my fuge. I am now convinced I had a bad test kit. I used the API test kit last night and its saying about 8.2. Link to comment Share on other sites More sharing options...
Origami April 10, 2009 Share April 10, 2009 What kit were you using before. The new reading's much more reasonable. Link to comment Share on other sites More sharing options...
sen5241b April 10, 2009 Author Share April 10, 2009 I was using the strip tests. They seemed to work fine until recently. Link to comment Share on other sites More sharing options...
rioreef April 10, 2009 Share April 10, 2009 Open a window if you have not near the tank. Getting outside air will help. Perform water changes. Topoff water will generally have a neutral pH unless you add something to increase the pH. Over time this could cause a slow drop off too. Link to comment Share on other sites More sharing options...
JMsAquarium April 11, 2009 Share April 11, 2009 But what causes Alk to fall and how do you boost it? I'm trying to get to the root cause. Same as with Calcium, all corals consume Alk to grow. I supplement mine with Arm & Hammer baking soda. Here's a link to Randy Holmes-Farley recipe. An improved home made two part solution Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now