There is a calculator. Here is the link. The problem many people seem to have is the differences in tanks parameters. Should I choose EI, low/light, PPS because I have XYZ? I am in the process of writing another calculator. I intend to add a wizard to ask these questions and suggest a good starting point to work from. Carlos (Wet) has been a great help with this endeavor thus far. Beyond that the calculator is very helpful and accurate. Where do you start?
You have a moderately planted tank. The plants are rather undemanding. I would start with 1/3 or so of the EI dose to start. Once you see how your plants respond you can slowly reduce that dose until you see a change.
Using that calculator you can choose EI low light weekly. There is another option you can start with. Choose EI daily and dose that amount every other day. It's a little more than you need but won't cause any problems what so ever. I like dosing something every day for several reasons.
The traditional EI method requires weekly water changes. This is important if you choose those doses from the calculator. If you want to modify the water change schedule you can look at the levels that will be expected in this calculator. Our goal here is to maintain a range of nutrients listed in the original post.
So basically, if you're willing to do weekly water changes I would choose the daily dose and use that every other day (more than you need but not harmful). We want to start above that barrel. Then decrease and find that critical point where we see changes. Do we need to reduce doses? Honestly I don't see any reason to. The levels are not toxic to fauna or flora. Is it expensive? Not at all. Do we need this much fertilizer. No, but is there any harm?
The entire point to this method is to supply non limiting nutrients. Then we can work on more important things like CO2 and basic gardening. Nutrients are the easiest part. We can tinker with various levels and argue over other aspects but the fact always remains the same. Just dose enough fertilizers for the plants needs.
Using EI low light weekly or daily dosing using that amount every other day, schedule below, will provide appropriate nutrients for any plants you may have.
Sun 50% water change (GH booster)
Does this make sense?
This is a good way to look at it.
Even if you under dose, the effects of adding ANY ferts will be positive on growth.
The only question is, are you adding enough to have independence from ferts?
Or are you still adding limiting fert values?
Liebig's law needs brought into the conversation.
This is the entire point of EI/Hoaglands nutrient modified solution, the idea of a non limiting fert routine. Dupla, Tropica both address this as does PMDD.