dkh is tooooo high

Reef Aquarium & Tank Building Forum

Help Support Reef Aquarium & Tank Building Forum:

eastonreef

Well-known member
Joined
Jan 5, 2006
Messages
49
Location
easton pa
my dkh is way tooooo high! i have done 2 water changes this week and plan to do one later today , but that has not helped. here is what i have:

dkh - 16 (should be 2.9)
mag - 1350
cal - 500
ph - 8.2
no3 - 0

i tested my ro water (before adding salt) and it is 1.0
i then tested water i made with instant ocean and it is 10.6

i am concerned because i have no polyp extension even on my millies. how do i lower the dkh??? is there something i can add to lower it??

please help
 
you might think about doing water changes to lower your CA level and it get back in line so your ALK will be closer to balanced. At least that is what I would do.
 
Eastonreef,

It sounds as if you are slightly confusing your measurements on your Alkalinity. There are 2 "most common" measurements when measuring Alkalinity. dKH, and meq/L. They both measure the same thing (alkalinity) but using a different scale.

Not sure if this will work correctly here, but here is a side-by-side compairison, so you can relate those 2 readings to one another;

KH value in dKH Alkalinity in meq/L
16.0 ----- 5.71
15.7 ----- 5.60
15.4 ----- 5.49
15.0 ----- 5.37
14.7 ----- 5.26
14.4 ----- 5.14
14.1 ----- 5.03
13.8 ----- 4.91
13.4 ----- 4.80
13.1 ----- 4.69
12.8 ----- 4.57
12.5 ----- 4.46
12.2 ----- 4.34
11.8 ----- 4.23
11.5 ----- 4.11
11.2 ----- 4.00
10.9 ----- 3.89
10.6 ----- 3.77
10.2 ----- 3.66
9.9 ----- 3.54
9.6 ----- 3.43
9.3 ----- 3.31
9.0 ----- 3.20
8.6 ----- 3.09
8.3 ----- 2.97
8.0 ----- 2.86
7.7 ----- 2.74
7.4 ----- 2.63
7.0 ----- 2.51
6.7 ----- 2.40
6.4 ----- 2.29
6.1 ----- 2.17
5.8 ----- 2.06
5.4 ----- 1.94
5.1 ----- 1.83
4.8 ----- 1.71
4.5 ----- 1.60
4.2 ----- 1.49
3.8 ----- 1.37
3.5 ----- 1.26
3.2 ----- 1.14
2.9 ----- 1.03
2.6 ----- 0.91
2.2 ----- 0.80
1.9 ----- 0.69
1.6 ----- 0.57
1.3 ----- 0.46
1.0 ----- 0.34
0.6 ----- 0.23
0.3 ----- 0.11
 
Last edited:
the kh value in dkh was 16.0
alkalinity in meg/l was 5.71 = too high

the calcium at 500 i did not see as a problem . i have sps in the tank and thought 500 would be a good thing. what should it be?

also if the new water i am mixing is high water changes wont help. i dont get it??? :(
 
What salt are you using? I know that various salts have different levels of Alkalinity, Calcium & Mag.

I use I O (Instant Ocean), which tends to be 8.5dKH, 350Calcium, and 1100Mag... when mixed to 1.026 Specific Gravity.

Also, when you do mix up your water-change water... be sure you aerate it well over night, while mixing. This helps ensure everything is well mixed, as well as blowing off any excess CO2, and oxygenating it nicely for you.
 
What name brand test kits are you using?
as mentioned by Steve & Ed make up large volumes of water, don't add supplements. Calcium levels over 450 is getting high, precipitation could happen at this point, you will cake up everything if this happen. What have you added to get it like this in the first place?
 
My first assumption is that your test is off. If you tank has normal levels of CO2 then your ph would be elevated to around > 8.5 at 16.0 dkh. If you test is correct then I would do a 20% water change. The Alk will fall and it will fall relatively fast, maybe 2-3 days.
 
i have been using a cal reactor --which i shut off today

i use I O salt... i mix overnight with a pump in a large plastic garbage can with a heater in it. is this enough to aerate?

i am using salifert test kits -- i retested with a second salifert kh/alk test and it is the same....

i have a 90 gal tank with a 30 gal fuge -- i use a skimmer and have a mesh bag in the fuge with carbon in it. lighting = (2) 250XM metal halides.

i really appreciate all the help
 
Sounds like your carx is just cranked up to high. Water changes will definatly bring it down quick.

Don
 
i use I O salt... i mix overnight with a pump in a large plastic garbage can with a heater in it. is this enough to aerate?

Heating and overnight mixing are the best way. I also have added a small airpump, so my mixing pump can churn in added air overnight as well.

I agree with Don, sounds like your Calcium Reactor is set too high... and a couple water changes should get things back into control for you.
 
regal tang
bicolor cleaner wrasse
pink margin wrasse
perk and osc pair
mandarin
lawnmower blenny

gbta, rosebta, sabea ,, cleaner crew
assorted lps and sps --- zoas, xenia. rics
 
hey easton seems like the advice given here is right on the money. the water changes will bring down your alk. My only concern would be where did it come from in the first place. I am under the impression that the high calcium levels would drive up the alk and they need to be proportianate. I usually run my calcium a little lower I do not have the sps you do. I run calcium at 400-420. I usually do not have to add anything until i do water changes. I then add kent turbo calcium to my make up waterto get as close to the tank params as possible. If you search the chemistry forum boomer has some pretty good data there that explains the chemical relationships between alk calcium and ph. some good reading a little complex but good info.:D
 
sorry you already posted here in the chemistry section. BOOOOMER should be chiming in anytime soooooon.:D
 

Latest posts

Back
Top