you can always use math to help get you we're your going. How stong is your ammonia, here in Germany I get it at 50% strenth which is 500mg/L which also happens to be 500ppmI believe (can anyone else verify this?). In the states most ammonia is sold at approx 8% which would be 80mg/L, there are 3.785L in a gallon, so you would multiply 80(or whatever your percentage times 10 happens to be) by 3.785 to get ml/gallon. At our rate of 80mg/L it becomes 308mg/gallon. Now remember that should be your straight solution strength, there are 764 teaspoons in a gallon and you have only added half of that so you have to double that number (1528) and divide 308 by it to get your ppm
. So you should have about .2ppm in your bucket. If it happens to actually be 100% (you would most likely be wearing a mask and heavy gloves to deal with it) you would have 2.4ppm. Actually all of these numbers would be for a gallon bucket and i just remembered you have a 2 so looking at .1ppm and 1.2respectively.
I did this with my 7.5gal tank and started with a 7% ammonia which was what i was planning.