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special_k
11-20-2017, 01:36 PM
Hello all, I search the forum but did not find a good answer so here it is:

Finding the right ammonia is a pain so I decided to cycle the tank with pure Ammonium Chloride (NH4CL) this time. But the dosage calculation is something I'm not too sure.

System total volume is 350l. In order to reach 2mg/l concentration of ammonia, how many grams of NH4CL powder shall I put in the water? that's 0.7g of NH3-.

Thank you!
Clawhammer
11-20-2017, 01:39 PM
I have never used NH4Cl before but you can always add a pinch, wait a couple minutes, then test. No fish = very little risk
DJW
11-20-2017, 02:29 PM
You wouldn't add 700 mg because only 1/3 of ammonium chloride is ammonium, the other 2/3 is chloride. For 2ppm add 2.1 grams of the powder.
special_k
11-20-2017, 03:00 PM
You wouldn't add 700 mg because only 1/3 of ammonium chloride is ammonium, the other 2/3 is chloride. For 2ppm add 2.1 grams of the powder.

Thank you for the reply but how did you come up with 1/3 and 2/3?
DJW
11-20-2017, 03:28 PM
You have to look at molecular weights. The ammonium ion has a mass of 18 (NH4 = 14+4) and chloride has atomic weight of about 35. So the weight of ammonium (18) divided by the total weight of NH4Cl (53) is 0.34... or about a third.
special_k
11-20-2017, 05:00 PM
You have to look at molecular weights. The ammonium ion has a mass of 18 (NH4 = 14+4) and chloride has atomic weight of about 35. So the weight of ammonium (18) divided by the total weight of NH4Cl (53) is 0.34... or about a third.

Thank you! I wasn't paying attention in my highschool chemstry class :D
special_k
11-20-2017, 05:00 PM
One more question. Do I mix the powder with small amount of water then dump it in the tank or I can put the power in the tank directly?
Clawhammer
11-20-2017, 05:06 PM
One more question. Do I mix the powder with small amount of water then dump it in the tank or I can put the power in the tank directly?

Direct
Megalodon
11-20-2017, 05:13 PM
2.673 mg
special_k
11-20-2017, 05:24 PM
2.673 mg

what is this number? 2.673 mg/l for cycling?
Megalodon
11-20-2017, 08:37 PM
what is this number? 2.673 mg/l for cycling?

2,673 mg of NH4Cl will result in the addition of 2 mg/L ammonia to 350 liters of water.

Sorry, spreadsheet was set to the wrong unit.

It's actually a spreadsheet for calculating how many grams of NH4CL, KNO2, NaNO2, (NH4)2SO4, KNO3, KMNO4, or KCl to add to a certain volume of water to create a calibration standard.
special_k
11-21-2017, 12:55 PM
2,673 mg of NH4Cl will result in the addition of 2 mg/L ammonia to 350 liters of water.

Sorry, spreadsheet was set to the wrong unit.

It's actually a spreadsheet for calculating how many grams of NH4CL, KNO2, NaNO2, (NH4)2SO4, KNO3, KMNO4, or KCl to add to a certain volume of water to create a calibration standard.

You have a spreat sheet for this? Great to have someone working with Chemstry here.