How much Green Light Stump Remover should I add?

[Paul]

The Sticky "Fertilizer Recommendations and Info" is very helpful, but I have one question: roughly how much Green Light Stump Remover (KNO3) should I add to a 30 gal. tank? Can someone add the answer to this question to the sticky, which gives dosage recommendations for the other recommended ferts? My nitrate level is around 5 ppm, and I'd like to add KNO3, as recommended by PlantBrain and others. I'm going to use trial and error, but it would be helpful to have some guidelines as to how much to add.

Thanks.

[ChicoRaton]

I'm a bit rusty on stoichiometry but I'll give this a shot. A gallon of water is 3.7854 liters, which has a mass of 3785.4g. So, to increase NO3 by 1ppm, you need to add 3785.4/1,000,000= 3.784mg per gallon of water of NO3.

This is wrong!
deleted because of utter inaccuracy-- I will post the correct math in a minute



Edit: Oh my god, I used the atomic number instead of the atomic weight for all that. it's all totally wrong. Give me a minute....

[ChicoRaton]

OK, so we want 3.784mg/gal NO3- to increase the level by 1ppm.

NO3- weighs 52g/mol, and K+ weighs 39g/mol. so KNO3 weighs 91g/mol. NO3 is therefore 52/91, or 57% by weight of KNO3.

3.784/0.57=6.64mg/gal KNO3 to raise NO3- levels 1ppm.

You have a 30 gal tank, so 6.64*30=199.15mg KNO3 to raise your nitrate 1ppm. W'll make things simple and say .2g per 1ppm.

If you don't have a scale that weighs things that accurately, make a solution of 100g KNO3 in a liter of water (It will dissolve. KNO3 is very soluble.) This solution is 10%KNO3. So every teaspoon (5ml) of this solution contains .5g KNO3, and will raise the NO3 level of 30 gallons of water by (.5/.2)=2.5ppm

[Rex Grigg]

½ teaspoon will give you 15 ppm in 30 gallons of water.

[Paul]

Oops - I added 1 tsp. KN03 before I read these posts. The nitrate reading is now somewhere in the 20-30 ppm range. I hope I haven't killed any fish.

Thanks for the replies. It would be nice if this information could be added to the Sticky - preferably in original post. But I guess the moderator would have to do that.

[Rex Grigg]

Read my Guide. The information is in there. And there is a link to a down loadable nutrient calculator. Get the calculator.