Quick question,
Tom has mentioned in different posts that aquatic plants are usually around 7-1-8 N-P-K by mass. That would mean that dosing those nutrients in that ratio would be ideal, wouldn't it? Not necessarily for plant growth, but just so that you aren’t needlessly wasting any nutrients. My question is this. The N-P-K ratio is a ratio of Nitrogen-Phosphorus-Potassium like it is for land plants, not NO3-PO4-K (Nitrate-Phosphate-Potassium), like we calculate and dose for right? So to get a true ratio for ppms of Nitrate-Phosphate-Potassium you have to factor in the Oxygen components and their masses to get a true ideal ppm ratio?
I am asking because Tom has mentioned that you actually get plenty of potassium just by dosing KNO3 for nitrate, and that would only be true if the N-P-K ratio was actually for Nitrogen-Phosphorus-Potassium. I just want to make sure I am not under dosing Potassium and/or confirm that if I dose KNO3 for nitrate that I don’t need to bother with any additional potassium fertilizer.
With my quick calcs, I came up with a converted ratio of about 31-3-8 for a mg/L or ppm comparison of NO3-PO4-K for ideal dosing. That ratio would explain why Tom has said that dosing potassium in addition to what is obtained from KNO3 is unnecessary.
I realize that what matters most is making sure there is at least some of each nutrient and the ratio isn’t really critical, but I am mainly doing this as my way of trying to create the most nutrient balanced “leftover water change water” for use on my houseplants and yard plants. Also it can save me some money on ferts when I eventually start adding a few more planted tanks to the mix too, haha.
I am also trying to get my dosing as consistent as possible so that I can pretty much test only nitrate levels (if I ever need to), and easily know that if I have enough that all the other nutrients are all fine to help with troubleshooting.
Any confirmation/correction would be much appreciated.
Have a good one, Jeremy
Tom has mentioned in different posts that aquatic plants are usually around 7-1-8 N-P-K by mass. That would mean that dosing those nutrients in that ratio would be ideal, wouldn't it? Not necessarily for plant growth, but just so that you aren’t needlessly wasting any nutrients. My question is this. The N-P-K ratio is a ratio of Nitrogen-Phosphorus-Potassium like it is for land plants, not NO3-PO4-K (Nitrate-Phosphate-Potassium), like we calculate and dose for right? So to get a true ratio for ppms of Nitrate-Phosphate-Potassium you have to factor in the Oxygen components and their masses to get a true ideal ppm ratio?
I am asking because Tom has mentioned that you actually get plenty of potassium just by dosing KNO3 for nitrate, and that would only be true if the N-P-K ratio was actually for Nitrogen-Phosphorus-Potassium. I just want to make sure I am not under dosing Potassium and/or confirm that if I dose KNO3 for nitrate that I don’t need to bother with any additional potassium fertilizer.
With my quick calcs, I came up with a converted ratio of about 31-3-8 for a mg/L or ppm comparison of NO3-PO4-K for ideal dosing. That ratio would explain why Tom has said that dosing potassium in addition to what is obtained from KNO3 is unnecessary.
I realize that what matters most is making sure there is at least some of each nutrient and the ratio isn’t really critical, but I am mainly doing this as my way of trying to create the most nutrient balanced “leftover water change water” for use on my houseplants and yard plants. Also it can save me some money on ferts when I eventually start adding a few more planted tanks to the mix too, haha.
I am also trying to get my dosing as consistent as possible so that I can pretty much test only nitrate levels (if I ever need to), and easily know that if I have enough that all the other nutrients are all fine to help with troubleshooting.
Any confirmation/correction would be much appreciated.
Have a good one, Jeremy