extremely high kh

[datguy]

I have kept a reef tank in the past and am restarting. I have a new tank set up and has cycled for 30 days. I have PH, Calcium, where I want them. I have a huge kh problem. I have never saw it so out of wack before in past keeping.

I have two specific questions
First is without adding any additives to the tank or doing water change, will the buffering capacity of the tank weaken over time, dropping the kh toward 12 dkh with only live rock and crushed coral substrate? (no animals or coral)

I am aware of large water changes to help kh, and I am going to guess the answer is no, that it would not drop naturally over time without any livestock.

Second is at the gap between normal max @12dkh and my current @24dkh, at what level does it become toxic or cause death among fish, inverts, and coral?

I have heard of people with a 16 dkh, with livestock looking to lower it, so is 12-16dkh the range of undesired, yet not deadly.

I am sure this is going to reauire a huge fix, but thanks for any help in advance.

 

[reef lover]

Any way its a testing error? I think at 24 dkh it would be precipitating into the water column.

 

[Geebs19]

Any way its a testing error? I think at 24 dkh it would be precipitating into the water column.

Agreed, that seems super high unless something was dosed that high.

 

[datguy]

I dosed too much superbuffer dkh. I want to know if it will decrease from 23 to 12 where it won’t kill livestock and soft corals. There is only rock and crushed coral in the tank as it is a new setup. I know what I did wrong and how stupid it is. Is the water all trash or will it drop without livestock? I have never messed this parameter up will have lost 50 gal of prepared water and be unable to put livestock in until I fix it or it goes down significantly by natural causes. I am sure there needs to be a creature to use it up....so I am most likely screwed. Back to square one.

 

[reef lover]

Yes numbers wont drop with nothing to use it..so a big water change is do.

 

[Crazeh]

You can always test in a few days and see how fast it comes down but as per above post with nothing to use it, it's unlikely it will.

I think you can add hydrochloric acid to reduce Kh but it will also reduce pH. Maybe something to research though (it's nothing I've done before so don't blindly dose the tank).

Easiest low risk method is to just reduce through some water changes.

Apologies not sure about at what level it becomes dangerous - my tank runs on the lower side of the alkalinity margin.

 

[datguy]

Thanks, I checked calcium, and dkh, and after bringing calcium up slowly the dkh went from 24 to 20 to 18 to 16, within 24 hrs. The calcium is now at 420, I am done messing with that. Since I have never messed up this parameter in the past. I looked all over for info on a better understanding of ph, dkh, calcium, mag relationships. It is interesting to say that should the dkh ever go above 12, there is not much in terms of a fix, other than liquid calcium, or water changes. I have turbo calcium and used in the past, I read that if dkh is high adding that won’t decrease the dkh, but I did cause it is my only calcium source. I was going to change the water out over the next 2 weeks since, and since I messes up I figured why not experiment with it. Adding calcium carbonate, with low ph, very high dkh, brought it down without clouding up my glass, equipment, or water. So I lose a few tsp of turbo calcium in the process...it was interesting to see that dkh level fall even without any livestock in the tank during cycle. Ph may get in the range of 8.2 from its current 7.8 if I wish upon a star as c02 leaves the tank along with bringing my salinity from 1.024 to 1.025. I am going to let it sit for a week or two before I do a 50% water change and recheck ca, dkh, and ph and see if somehow they right themselves after the addition of ca to the tank. One thing I still cannot find and prob RHF knows is, at what level does dkh begin to negatively and noticabally affect fish, coral, inverts, plants within a system. I saw a few posts where established tanks spiked to 16 dkh briefly and did not see die off, so my guess is although outside of the high range of 12 dkh, apparently up to 16 dkh may be the threshold where life begins to end. I am assuming it is due to the high density of disolved solids in the solution and inability to transfer gasses within as well. I hope to never have to post something so stupid again. Took me back to rookie mistakes when I first begin keeping and kept a tank thru college. Definately made less mistakes after the first 6mo to a year.