Low Alkalinity

Gnawsome · Mar 7, 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, so as far as I understand there is nothing that could be using the calium/mg etc.

Flippers4pups · Mar 7, 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, so as far as I understand there is nothing that could be using the calium/mg etc.

Not sure. Try making up a small amount of new saltwater and test it for alkalinity. See where it's at fresh.

On a side note, what alkalinity kit are you using.

Gnawsome · Mar 7, 2019

Flippers4pups said:
Not sure. Try making up a small amount of new saltwater and test it for alkalinity. See where it's at fresh.

On a side note, what alkalinity kit are you using.

10-4 I'll mix up some salt water and test it. I'm using red sea titration test.

KrisReef · Mar 7, 2019

Some of those bags are made to mix the whole sack at one time, so the mg may all be at the bottom of the sack? I’ve seen this before, and they may have put all the mag flake in another sack.

. -
I’ve seen that too!

Same could be for the buffers?

Gnawsome · Mar 7, 2019

KrisReef said:
Some of those bags are made to mix the whole sack at one time, so the mg may all be at the bottom of the sack? I’ve seen this before, and they may have put all the mag flake in another sack. . -
I’ve seen that too!

Same could be for the buffers?

Is there some type of identification to know you're supposed to mix the whole thing at once? Mine does not say anything about that on the bucket. It does say to mix up at least 12oz at a time, which I definitely did.

Adamantium · Mar 7, 2019

I don't have an answer, but the same thing happens to me with Reef Crystals. My tank sits around 8.5, but fresh SW mixes up to b/w 12 and 14 dKH.

KrisReef · Mar 7, 2019

The red sack I was thinking about was marked “ commercial” on it, for mixing 200 gallons at one time. I don’t know if they make a commercial bucket?

Gnawsome · Mar 7, 2019

KrisReef said:
The red sack I was thinking about was marked “ commercial” on it, for mixing 200 gallons at one time. I don’t know if they make a commercial bucket?

It's a tiny bucket for making UP TO 55 gallons. The salt water should be ready tomorrow morning and I can give it a test.

Gnawsome · Mar 8, 2019

Ok, so I just tested the Alkalinity of the new salt water and it comes to exactly 12dkh.

So to recap. New tank tests for 7.5dKh. New Salter water before going into tank tests for 12dKh. Where is the dKh going ?! There is no livestock/corals/algae at all in the tank.

Adamantium · Mar 9, 2019

Gnawsome said:
Ok, so I just tested the Alkalinity of the new salt water and it comes to exactly 12dkh.

So to recap. New tank tests for 7.5dKh. New Salter water before going into tank tests for 12dKh. Where is the dKh going ?! There is no livestock/corals/algae at all in the tank.

How long after mixing the water are you testing?