Very low KH & high PH

trippclark

Member
I went out of town for nearly two weeks and upon returning my water tests showed VERY low KH (3) and PH (7.8 or 7.9). I used Kent Superbuffer dKH for 3 - 4 days at the prescribed dosing. The PH rose to 8.6 but KH stayed at 3. I have also done three water changes of about 12 gallons, 12 gallons, and 15 gallons over a period of about 2 weeks (55 gallon tank). Each time I test the new water (PH 8.3, KH 8 or 9, and CA 380 - 400). My tank CA levels during this time have ranged from 340 - 390. I am dripping Kalk and using RO/DI water. STILL, my tank KH stays at about 3. After water changes it briefly rises to 5 or so but drops back to 3 within a day. PH is also staying high at 8.5 - 8.6. I have not added any more of the Kent Superbuffer dKH in 2 weeks because I attribute the higher than ideal PH to it and see no positive impacts on KH. I am readying another 14 gallons of water now with plans of another water change, probably Tuesday, but am perplexed as to why I am not seeing PH drop or KH rise. Any ideas as to what I am missing, or suggestions to remedy this????
 

trippclark

Member
Originally Posted by coraljunky
http:///forum/post/2498548
http://home.comcast.net/~jdieck1/chemcalc.html
Have you tried another test kit?
Coraljunky,
My PH and CA kits are Salifert and my KH is Tetra. My preference is Salifert but I was unable to find a Salifert KH kit. Anyway, the issue may be my kit, but I don't think so since my new water fresh from mix and RO/DI have all good readings. HOWEVER, when I add it to the tank, my tank readings fail to improve. I am wondering if there is something in the tank or set of conditions that would cause this . . . and if there is something to fix it that I may have not tried.
Also, am I correct to stop adding the Superbuffer dKH? My fear is that continuing to add will cause PH to spike enen more . . . right or wrong????
 

coraljunky

Active Member
I would def stop adding buffers until you find the culprit. lordlocks does have a good point, do you have a magnesium test? I just don't understand how your ph can be that high with cal and kh being so low
Did you try the link I posted?
 

trippclark

Member
Originally Posted by lordlocks
http:///forum/post/2498552
try testing your magnesium, if its low bring it up to around 1250 ppm and then test and use buffer.
Mg is at 1110 on a Salifert test kit. That is lower than ideal, but is it low enough to cause the problems I am experiencing?
 

trippclark

Member
Originally Posted by trippclark
http:///forum/post/2498574
Mg is at 1110 on a Salifert test kit. That is lower than ideal, but is it low enough to cause the problems I am experiencing?
Just added a dose of 60ml of Tech-M. This is the dosing recommended daily on the product label in order to raise Mg about +18 daily. Given that dosing it will take me about 8 days to get to 1250.
 

trippclark

Member
Well it has been 11 days since last post. I did the additional water change mentioned earlier. Using the Reef Chemistry Calculator suggested by coraljunky and following up with doses of Kent Tech-M, Kent Liquid Calcium, lots of Baking Soda (15 tsp+ over time), and just one dose of Kent Superbuffer (1 tsp) when PH crept down to 8.0.
Now CA is at 400, MG is at 1280, PH is around (slightly below) 8.3, and KH is at 5.0 after rising to a recent high of 7.0 the day before yesterday. What gives? Any other ideas on getting KH to stay at a good level. My thought is that 7.0 should be the low end of what I am shooting for, not the top, and that 5.0 is not acceptable (although indeed better than the 3.0 I was at 2 weeks ago).
 

chuckcac

Member
have you tried Baking Soda?
Baking soda = Sodium Bicarbonae... could help with KH
still using that Tetra kit?.....
 

trippclark

Member
Originally Posted by chuckcac
http:///forum/post/2516050
have you tried Baking Soda?
Baking soda = Sodium Bicarbonae... could help with KH
still using that Tetra kit?.....
Yes to both. Over the past 12 days I have added 15+ tsp of baking soda (not all at once of course). When I do, KH goes up to 7 or so immediately but is back down to 5 in a day or two.
Still using Tetra kit.
The Tetra kit reads 10 or 11 on new water from mix.
 

chuckcac

Member
weird...... i'm still in accord with trying another test kit.... Got a buddy that does saltwater? - bring some water to them - or the LFS and have them test for KH....
do you have substrate and/or live rock?
 
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