Calcium / alkalinity
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Topic: Calcium / alkalinity
Posted By: chuckfu5
Subject: Calcium / alkalinity
Date Posted: February 21 2017 at 8:59pm
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Guys, 4 month old tank, 13.5 gallons. Heavily stocked with coral and a couple fish. Parameters are as follows PH 7.8 in the morning, 8.2 in the afternoon Ammonia 0 Nitrite 0 Nitrate 5 Phosphate 0 Calcium 380 - 400 DKH 5 I've started dosing Kent's 2 part for the calcium...its slowly increasing but cannot get the alkalinity to move. Any thoughts on what's going on? I do a couple gallon water changes every 3 or 4 weeks. Trying to learn about water chemistry and just trying to understand and do the best that I can. Everything appears happy and growing. TIA |
Replies:
Posted By: 1stupidpunk
Date Posted: February 21 2017 at 9:19pm
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I don't know all the scientific jargon but its not uncommon for Ph to shift during hours of darkness. Photosynthesis doesn't take place during lights out (unless your running a reverse daylight refug) so the corals/macro aren't creating oxygen. (most corals get there color from the zooxanthellae algae which is photosynthetic which creates oxygen). Most of our bigger reefs have refugiums and large quantities of water so the drop isnt as significant. On a 13.5g (i assume you dont have a large sump with it) the change will be much more noticable... as long as the the drop and the peak are within acceptable ranges I wouldnt be to concerned. |
Posted By: MadReefer
Date Posted: February 21 2017 at 9:21pm
| Check magnesium and you might want to slow the addition of calcium while you bring up the alk. From my understanding, alk and cal will combine and precipitate out if one value is too high and this happens at lower levels if magnesium is low. |
Posted By: 1stupidpunk
Date Posted: February 21 2017 at 9:22pm
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Heres a few links you can read if you really want to dive deeper into the daily pH shift.... http://www.reefkeeping.com/issues/2007-05/rhf/#6 http://www.melevsreef.com/node/1739 |
Posted By: phys
Date Posted: February 22 2017 at 1:57am
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You'll want to bring the kh up to at least 7 to match a calcium level of 400. 7.5 would be better. Also, kh is a buffer to help keep the ph level from swinging too much. Strontium and magnesium help that to an extent also. Try to get the kh up to the point that matches the calcium and then watch it for 3 or 4 days without dosing to see how much your tank uses and then dose to keep that stable. Or slowly add more kh over the course of a week, check, and if it's still dropping, increase the dosing, and repeat until you have it in check. Then you'll need to continue checking because as the corals get bigger and the more you add, the more they'll be eating up. You may need to increase then two part in the calcium due to some systems eating more kh than calcium. It's not always a 1:1 ratio. You'll also want to get a second check to verify your tests are accurate. Sometimes a bad test kit can give you bad values. |
Posted By: Reefer4Ever
Date Posted: February 22 2017 at 5:59am
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Definitely get another test kit or take it to an lfs for a second test, at 5 dkh those corals should be very unhappy. What salt are you using? Move the dkh at no more than 1 dkh per day. What type of corals are you keeping? What are all your parameters in your water that you are testing for? As you have read here other things in the water whether I high or low can make it hard to get the dkh up. ------------- 90 gal reef w/refugium 24 gal softie tank 11 gal nano anemone tank 5 gal fresh water |
Posted By: Krazie4Acans
Date Posted: February 22 2017 at 10:00am
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I second Madreefer. Check your Mag level. I bet it is low. I would also look at switching to a salt that is higher Alk level to help keep it at a higher level once your dosing gets the levels back in line. ------------- My ocean. 90g (yup, won it!), 40g, 28g, & 10g Systems PADI Advanced Open Water http://utahreefs.com/forum/forum_posts.asp?TID=63568&title=krazies-nano-paradise" rel="nofollow - Tank Thread: |
Posted By: kevin.st
Date Posted: February 22 2017 at 10:04am
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I would definetely have someone else test your water to verify. I would very slowly raise that dkh. Mag/calcium/alk are interdependent, btw.
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Posted By: Krazie4Acans
Date Posted: February 22 2017 at 10:23am
Interdependent is good until you try to change them all at once.  I find it easiest to fix mag first for two reasons. First you can dose quite a lot of it without any negative effect on the system. Second because I have found it near impossible to bring Alk up if Mag is too low. So I bring up Mag, then verify calcium (it will probably change some with the Mag level corrected) and correct as needed and then start slowly bringing Alk up no more than 1dKh per day and checking the calcium and mag as the Alk comes up (again they will change as the alk level returns to a proper level). ------------- My ocean. 90g (yup, won it!), 40g, 28g, & 10g Systems PADI Advanced Open Water http://utahreefs.com/forum/forum_posts.asp?TID=63568&title=krazies-nano-paradise" rel="nofollow - Tank Thread: |
kevin.st wrote:Posted By: Mark Peterson
Date Posted: February 22 2017 at 11:50am
Really good advice by everyone so far.  What appears to have happened is that water changes have not kept up with demand for these critical components. The Alk, Ca (possibly Mg as well) levels have slowly fallen over the 4 months of this tanks existence. You were correct to start dosing the 2 Part additives. As mentioned above, when one level, Alk in this case, is further out of range than the other, that part of the two part system needs to be dosed more than the other. Regarding Magnesium, Kent Part A also contains Mg so it supplements both Ca and Mg. But that's not to say that Mg can still get low and require dosing alone. Luckily, inexpensive and readily available Epsom Salt is what is used to increase Mg. One thing I would add is that coral can seem to be doing well even as the level of Alk declines to 5 dKH. They can handle the gradual decrease, but if left unchecked, a point will come where coral begin to die and the entire tank can crash due to the pollution (Ammonia -> Nitrite -> Nitrate, etc.) caused by decomposing coral. Fortunately, you have caught it just in time. My simple advice to avoid a problem and keep the tank healthy is: Double the amount of Kent Part B (Alk) added to the tank over the course of the next week. Continue dosing Kent Part A at the recommended dosage and check all three levels in a few days and again at the end of the week of dosing. Based on the results of the testing, dosing can then be adjusted as necessary to keep Alk in the range 8-11 dKH, Ca between 350-500 ppm and Mg in the range of 1200-1400 ppm. Keep your hands and arms inside the tank, have fun and enjoy the ride. Aloha, Mark  P.S. At this point in the life of this tank, the two most important levels to monitor are Alk and Ca. Mg is something that should be checked occasionally. All other tests become pretty much unnecessary from this point on. P.P.S. I just read the instructions on the Kent 2-part bottle. (It's an older label. They may have updated it since.) It's all good info except for some reason they omit the vital info about dosing different quantities of A and B when testing indicates that one or the other is lower. BTW, I love Kent Coral-Vite. It makes coral happier.
------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member
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Posted By: Hogie
Date Posted: February 22 2017 at 12:00pm
| Do you have a picture of the tank so we can see the livestock in it? |
Posted By: chuckfu5
Date Posted: February 24 2017 at 6:34pm
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So i cannot get the alk above six. Also since I've started dosing I've got a bright brown algae bloom going on the sand bed only. Any ideas on what's going on? Calcium is back up to 420 |
Posted By: phys
Date Posted: February 24 2017 at 7:18pm
| double check your test kit for alk.. it might be bad. How have you been dosing it? How often and how much have you dosed over what time period? |
Posted By: phys
Date Posted: February 24 2017 at 7:19pm
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Also, how long between tests and how long after dosing did you check? |
Posted By: Krazie4Acans
Date Posted: February 24 2017 at 7:19pm
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Have You gotten test results back on your water from another tester to verify that your kit is working correctly? What were those results? ------------- My ocean. 90g (yup, won it!), 40g, 28g, & 10g Systems PADI Advanced Open Water http://utahreefs.com/forum/forum_posts.asp?TID=63568&title=krazies-nano-paradise" rel="nofollow - Tank Thread: |
Posted By: Mark Peterson
Date Posted: February 24 2017 at 8:26pm
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------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member
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Posted By: chuckfu5
Date Posted: February 24 2017 at 8:30pm
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Aquatic dreams verified my test results yesterday. My test kit is reading accurate. I've been dosing Alk in the morning and testing at night. Testing calcium at night and then dosing it. I'm dosing 1 tsp of cal and alk daily. |
Posted By: Mark Peterson
Date Posted: February 24 2017 at 9:30pm
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------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member
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Posted By: Mark Peterson
Date Posted: February 24 2017 at 9:47pm
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------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member
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Posted By: phys
Date Posted: February 24 2017 at 10:02pm
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I'd bump your dosing up to 1.5 tsp of alk. I also wouldn't dose them so close together as was mentioned before. You re regimen is good, just increase the alk a bit. If its still not going up, do two tsp. Any more than that and you'll want to dose multiple times per day. I usually wait at least 20 min before doing a test just to make sure it's mixed completely into the system but how your testing is fine. Also, in such a small tank, be sure to watch the corals and fish to make sure the dosing amounts aren't causing issues with them. If they look stressed, reduce each dose and then dose more times per day to make up for it. |
Posted By: Reefer4Ever
Date Posted: February 25 2017 at 9:23am
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Agreed with Phys. Stability is essential imo. Dose more often smaller amounts to keep things from highs and lows. ------------- 90 gal reef w/refugium 24 gal softie tank 11 gal nano anemone tank 5 gal fresh water |