Hi @Mitchel Did you get the nitrate (NO3) reading from a water report or did you measure it yourself (measuring NO3 can be quite difficult with a test kit) ? Even if you know for sure its 15 ppm out of your tap, I would be cautious relying on "fertilizers" from tap water as it may vary quite a bit throughout the year. Personally, I would disregard it and just create a stock solution not taking the tap water NO3 level into account. Alternatively, you could factor it in a bit by just going a smidge lower with the NO3 with the stock solution than you otherwise would.If I want to make my nutrients I use dry salts.
But my tapwater also contains nitrates. (15ppm) Should I take this into account when creating a stock solution?
This is because I do a 50% weekly water change with tap water
Tia, Mitch
Can you post your water report here?If I want to make my nutrients I use dry salts.
But my tapwater also contains nitrates. (15ppm) Should I take this into account when creating a stock solution?
This is because I do a 50% weekly water change with tap water
Tia, Mitch
Can you not go RO all the way? This will in turn allow you to do whatever you want in terms of ferts without having to wonder how to reach a target that you will never reach simply because salt concentration in your tap water can and will inevitably vary during the course of the year.I think it's a bit tricky because I want to have a 'lean-dose' approach.
My target would be approx 7 ppm nitrates so I'll would have to work with 50% osmosis/tap water.
So I wouldn't have to use ferts for the NO3 because it's already present in my tap water (according to my water company)
I'd just use a <"complete fertiliser"> (including nitrogen (N)), but don't have a "target value" as such. You can use the plants to deplete the nitrate (NO3-) in the tap water and then use the <"Duckweed Index"> as an indication of when to add more fertiliser.I think it's a bit tricky because I want to have a 'lean-dose' approach.
My target would be approx 7 ppm nitrates
Can you post your water report here?
No, not really, you can use lean dosing with any starting water, you just need to <"watch the plants, they can't lie">.If you make your own nutrients, you can never achieve exact targets when you work with tap water. Hypothetically speaking, would a 'lean-dose' approach only be efficient if you work with RO water?
Yes, exactly that. It isn't that I'm not interested in water parameters, <"I'm very interested">, but I also realise that <"there are mechanisms"> you can use to give you a ball-park figure, and that <"ball-park"> is near enough.Can I then conclude that it does not actually have to be calculated so precisely,and that an approximation of a given ppm must be seen in a bigger perspective.
e.g. 15 ppm is perfect, but 10 or 20 is also good?
But only briefly, until the plants deplete it. So realistically that number is always shrinking until you add some more NO3-, either from your water change or from your fertiliser.But when I look at my commercial bottle of nutrition and it says: with every 10ml addition you get 15ppm nitrate in the water.
Fine, but if my tap water also contains 15 ppm, so I suddenly have 30 ppm in the water.
But ~no-one actually knows <"how much nitrate they have"> and the <"needs of plants will differ">, dependent <"upon their growth rate etc">. If you <"have these, (belonging to @Cédric )Same situation with the EI. Average targets for nitrate are 22.5 ppm. So if I perform a water change, 15ppm comes out of the tap and according to the EI, I get a total of 37.5ppm nitrate in my tank.
I know it's not all that important, and that you 'reset' everything with a weekly water change. But I find it very confusing when people say: your tank needs (as an example) 22,5ppm nitrates.
Hypothetically speaking, would a 'lean-dose' approach only be efficient if you work with RO water?