I do know and use that source but it is always good to look around a bit and compare total when shopping.
what you need will often be a bit different on tanks as it depends on what is going on in the tank. Lots of fish can make the need for some ferts like nitrate or phosphate low or totally unneeded. There will also be a big difference in what plants, how many, and what water. some plants slurp nitrate, others less. How much if any extra iron may depend on how much calcium you have as too much may make it hard for plants to take in the iron even if it is in the tank!
so does all this make it hard to use dry ferts? Not any more than if you use a simple mix and want to truly get the best performance in your plants. It does make it possible to increase the one item you want to try and then you can decide if it helped or did nothing.
Unless you know that you have too much nitrate, phosphate, etc. , I suggest getting the big three macros, NPK and the micros in CSM+Band possibly a bag of iron, just as a starter that covers almost all cases. MG is better bought in local store Epsom salt! You will likely find you can buy all these and it will last you years for the same price as a couple bottles of pre mix, so I favor stocking all the likely needs on one shipping charge, even if I find I don't need one as the fert itself is not very expensive. The water you get in pre mixed is pretty dang expensive compared to tap water!
My souce and suggested to check:
https://www.nilocg.com/product-cate...oducts/dry-fertilizers-for-planted-aquariums/
I just use kitchen spoons or pinch, dab, etc. as it is all very much an estimate and the amount is not something I find critical but I do want a consistent amount so I know what changes I make if any. I find it works for me to just dip a cup of tank water, mix it well and pour it in! The dry is mch easier to store than if I mix and sweat the PPM, etc. Since I can't actually what amount of tank water is in each tank, I do not look at PPM as being nearly as important as how green the plants look!
But this is the calculator which works for me:
https://rotalabutterfly.com/nutrient-calculator.php
AND then?
If things are not right ( and they are rarely perfect) one of these can help spot what changes you might like:
https://www.google.com/search?q=aqu...hUE04MKHWesDrsQ9QEIZzAH#imgrc=Vn4aQwqnj0DI2M:
