Help me Balance!

[JD'sReef]

6/10 - My specs were
KH: 8.7dkh
CA: 425ppm

6/14 -Today
KH: 10.0dkh
CA: 425ppm

I have heard some rumors about the Salfert KH test kits being bad, but is this reading possible if the kit is good.
I am currently adding 2tsp of kalk to my top off, so how could this be possible. The more and more I write this, the more I feel the test kit is bad; can someone reassure me on this issue.
Thanks,
J.

 

[Anonymous]

Those values seem relatively normal. I would also test for magnesium.

You could also test at your lfs or from another hobbiest as a cross check. Be sure to use the same test sample and do the tests at the same time. (Take you kit to the lfs or friend).

Also I have heard the kh can vary with the time of day (just like pH). So be sure to test at the same time of day.


my .02

 

[JD'sReef]

Thanks Beaslbob!
I definitely grasp you comments about the KH fluctuating with the time of the day. It only makes sense that if t he PH fluctuates with the light cycle, the KH would as well. My only comment is that you said that the values seem relatively normal; I though 7/8 DKH was the normal for my alk. I like my ca at 425ppm, but a KH of 10.0DKH seems a bit out of wack. If it is no biggie I think I will just leave it a wait for some new test kits.
Thanks,
J.

 

[Anonymous]

Thanks Beaslbob!
I definitely grasp you comments about the KH fluctuating with the time of the day. It only makes sense that if t he PH fluctuates with the light cycle, the KH would as well. My only comment is that you said that the values seem relatively normal; I though 7/8 DKH was the normal for my alk. I like my ca at 425ppm, but a KH of 10.0DKH seems a bit out of wack. If it is no biggie I think I will just leave it a wait for some new test kits.
Thanks,
J.

Actually the key to dosing from what I hear is maintaining the levels. 425 and 7/8 kdh is normal. But if kh drops then you dose the calcium and alk to keep both up. That way the tank's consumption determines the dosage. and the corals/corraline have the calcium carbonate they need and are using.

 

[leftovers]

Time of day has little to do with water hardness, little. Time of day does affect pH. Your water hardness test can be affected by when you dose or top off. Water hardness tends to drop as time goes by not increase and it will not vary much per day unless you are dosing or adding top off water like kalkwasser.

Your pH is greatly affected by the hardness (dKh etc) of the water along with the CO2 level of the tank, which is why during the day with lights your pH increases as CO2 drops and drops during the night as CO2 levels increase. Its a trivial amount but it can affect your pH by as much as .2 to even .4 over 12 hours in rise or drop the better buffered your water is the shallower the swing along with dosing your top off water at night with kalkwasser or other buffer to maintain your pH.

There tons of postings and articles on the advanced magazine discussing hardness, dosing and testing.

 

[JD'sReef]

Thanks Leftovers!
I may have just taken that test when the Kalk top off water was just added. I just got some new tests kits and I will use them and also turn off the kalk top off a few hours before.
Thanks,
J.