Donovan Nitrate Destroyer Acting Like Ca Reactor?

[JGT]

So I was noticing that my Calcium numbers were pushing the upper limits ~550 of where I want them to be, so I decided to stop dosing, let them fall gradually and then start back up. That was 3 weeks ago. I couldn’t understand how my calcium numbers were being maintained at those levels. Then it dawned on me. I’m doing carbon dosing via a Donovan Nitrate Destroyer (DND) and while 3/4 of the media is ceramic bioballs, I do have a 1/4 that is live rock rubble. Could the vodka/vinegar dosing be causing the DND to act like a calcium reactor?

 

[56longroof]

So I was noticing that my Calcium numbers were pushing the upper limits ~550 of where I want them to be, so I decided to stop dosing, let them fall gradually and then start back up. That was 3 weeks ago. I couldn’t understand how my calcium numbers were being maintained at those levels. Then it dawned on me. I’m doing carbon dosing via a Donovan Nitrate Destroyer (DND) and while 3/4 of the media is ceramic bioballs, I do have a 1/4 that is live rock rubble. Could the vodka/vinegar dosing be causing the DND to act like a calcium reactor?

I was actually thinking about using coral rubble for the same reason. I know aragonite will slowly dissolve in a DSB so I dont see why the same wont happen in a DND.

 

[JGT]

I was actually thinking about using coral rubble for the same reason. I know aragonite will slowly dissolve in a DSB so I dont see why the same wont happen in a DND.

Only problem is my calcium is through the roof. And it makes it hard to adjust. I guess my 2 options are to go to vodka-only for carbon dosing or remove the rubble.

 

[Randy Holmes-Farley]

if alk is not getting too high, the denitrator is not pushing calcium too high. It would only add 20 ppm of calcium for a 2.8 dKH alk boost.

 

[JGT]

if alk is not getting too high, the denitrator is not pushing calcium too high. It would only add 20 ppm of calcium for a 2.8 dKH alk boost.

That’s what’s weird. Seems like no effect on alk, only calcium which doesn’t make sense. Guess I need to look elsewhere. Thanks Randy.

 

[Randy Holmes-Farley]

That’s what’s weird. Seems like no effect on alk, only calcium which doesn’t make sense. Guess I need to look elsewhere. Thanks Randy.

It is either testing error for calcium, or a different source.

How are you dosing alkalinity?

 

[JGT]

It is either testing error for calcium, or a different source.

How are you dosing alkalinity?

Sodium Hydroxide.

 

[Randy Holmes-Farley]

Ok, and the calcium part?

 

[JGT]

Calcium Chloride pellets. I have a new Hanna reagent package which I am going to try and see if I get the same results. I will say my results have been consistent for the past several weeks so if it is me who is causing the testing error, I am at least…consistent.

 

[Randy Holmes-Farley]

What pellets? If you used anhydrous calcium chloride in a recipe that assumed it was a dihydrate, then calcium will steadily rise.

 

[JGT]

Gotta check but it’s what’s used as a snow/ice metering if that helps. Problem is I’ve had the calcium doser turned off for weeks now and the levels are still at 550.

 

[Randy Holmes-Farley]

Gotta check but it’s what’s used as a snow/ice metering if that helps. Problem is I’ve had the calcium doser turned off for weeks now and the levels are still at 550.

Ice melts can be the dihydrate or anhydrous. :)

 

[JGT]

Ice melts can be the dihydrate or anhydrous. :)

Here’s the ingredients but not really an issue as again, nothing dosed in weeks to probably a month now. Just did a new Calcium reagent test. Made sure to follow process to a T. Results: 567. Calcium is coming from somewhere. DND seems like the only option.

 

[Randy Holmes-Farley]

Ok, but when you use that, you use less than my standard recipe which is designed for 77% calcium chloride, not 92% which has less moisture and more solids in it. :)

 

[JGT]

Ok, but when you use that, you use less than my standard recipe which is designed for 77% calcium chloride, not 92% which has less moisture and more solids in it. :)

Yes, I follow your directions as if it were gospel. So the fact that this has some water in it makes it dihydrous?

 

[Randy Holmes-Farley]

Yes, I follow your directions as if it were gospel. So the fact that this has some water in it makes it dihydrous?

The calcium chloride dihydrate is about 77% calcium chloride and has 2 water molecules for each calcium chloride in the solid crystal.

Anhydrous versions have less water, more calcium chloride, and need less material to reach the same potency. It is not necessarily purer, just less water in the solid.

 

[JGT]

The calcium chloride dihydrate is about 77% calcium chloride and has 2 water molecules for each calcium chloride in the solid crystal.

Anhydrous versions have less water, more calcium chloride, and need less material to reach the same potency. It is not necessarily purer, just less water in the solid.

Gotcha. Science factoid for today:
I just thought of something but I have to go back to my calendar to confirm dates. I had an incident where my sponge created an air lock and my ATO emptied and dropped my SG to 1.023. I then added high octane saltwater to get my SG back to 1.026. The high octane would have had a higher level of Calcium in it as well. But, I would think that the drop in Calcium due to the ATO emptying would have offset that but maybe not?

 

[Randy Holmes-Farley]

Those effects should have offset if the initial and final sg were the same. :)

 

[JGT]

Those effects should have offset if the initial and final sg were the same. :)

OK, that was my initial thoughts. As you can see, I’m getting desperate.