dKH Magically Disappearing?

Gnawsome · Mar 8, 2019

Good afternoon,
I have a 20 gallon tank started 2 weeks ago with dry rock and dry sand. I dosed it with Ammonium Chloride to 4ppm. The ammonia has now dropped to slightly less than 1 ppm, and nitrites are 1+ppm. Nitrates are about 20ppm.

The salt I'm using is listed at 12dkh for salinity at 35ppt. When I test my tank it's at 7.5 dkh. Any ideas why it's so much lower than the salt box claims?

My salinity is at 35ppt. And the salt is Red Sea coral pro salt. There is no livestock in the tank and no algae, so as far as I understand there is nothing that could be using the calium/mg etc.

I made up some fresh salt water and tested it. It comes out to the expected 12dkh.

Is this normal? Does ammonia/nitrite interfere with any of this? Thanks!!!

intricate_reefer · Mar 8, 2019

I’ve been told bacteria use up carbonates during the nitrogen cycle. When I set up my 30 gallon I saw a drop in DKH, especially after I dosed bacteria. Now that it’s been set up for about 3 months with about 20 lps corals I get a drop of around .2 dkh a day which I attribute to the corals

Gnawsome · Mar 8, 2019

VaporCountry said:
I’ve been told bacteria use up carbonates during the nitrogen cycle. When I set up my 30 gallon I saw a drop in DKH, especially after I dosed bacteria. Now that it’s been set up for about 3 months with about 20 lps corals I get a drop of around .2 dkh a day which I attribute to the corals

Should I be dosing sodium carbonate to keep it at 8 until cycle is over? Or just leave it alone?

intricate_reefer · Mar 8, 2019

No should be fine, after you cycle is over I recommend a huge water change to take care of all the nitrites. That water change should bring up your dkh quite a bit using the coral pro salt

Hermie · Mar 8, 2019

How do you know your salinity is 35ppm ? I only ask because if your salinity measurement is "off" then it would lend that the dKH would be off by virtue of using less salt than you thought was necessary. I know you made the new batch of salt, I assume you also checked the salinity, but I thought I'd bring this up.

Gnawsome · Mar 8, 2019

Che

NotASpammerDude said:
How do you know your salinity is 35ppm ? I only ask because if your salinity measurement is "off" then it would lend that the dKH would be off by virtue of using less salt than you thought was necessary. I know you made the new batch of salt, I assume you also checked the salinity, but I thought I'd bring this up.

Checked with a calibrated refractometer. I calibrate it everytime I check salinity.

lapin · Mar 8, 2019

Gnawsome said:
Good afternoon,
I have a 20 gallon tank started 2 weeks ago with dry rock and dry sand. I dosed it with Ammonium Chloride to 4ppm. The ammonia has now dropped to slightly less than 1 ppm, and nitrites are 1+ppm. Nitrates are about 20ppm.

The salt I'm using is listed at 12dkh for salinity at 35ppt. When I test my tank it's at 7.5 dkh. Any ideas why it's so much lower than the salt box claims?

My salinity is at 35ppt. And the salt is Red Sea coral pro salt. There is no livestock in the tank and no algae, so as far as I understand there is nothing that could be using the calium/mg etc.

I made up some fresh salt water and tested it. It comes out to the expected 12dkh.

Is this normal? Does ammonia/nitrite interfere with any of this? Thanks!!!

Your tank will not be stable for a few months. Alk, Ph and the rest of you numbers will change with time, Its normal for a tank to use a lot of everything as new things grow. It will be an up and down. Do not try to chase any numbers with additives. Until you have a lot of SPS coral the Red Sea blue bucket should be fine. Coral pro is over kill and will elevate your numbers too much.

Gnawsome · Mar 8, 2019

lapin said:
Your tank will not be stable for a few months. Alk, Ph and the rest of you numbers will change with time, Its normal for a tank to use a lot of everything as new things grow. It will be an up and down. Do not try to chase any numbers with additives. Until you have a lot of SPS coral the Red Sea blue bucket should be fine. Coral pro is over kill and will elevate your numbers too much.

Thank you