Rotalabutterfly Vs. Aquarium Calculators

Now I'm confused. These two sites have some differences in the amounts of ferts to mix.
For instance, Rotala say to (mix 40.05 grams) of mgso4 in 250 mil water and dose 15ml to get 1.57ppm of mg per dose. That's 4.71 ppm per week.

Aquarium calculators says to (mix30 grams) of mgso4 in 250mil and dose 19mil to get 1.498ppm per dose and a total of 4.495ppm per week.

So which one is right??

Also, rotala doesn't give the mg from the trace. Aquarium calculators does.

Rotala says to (mix 4.95 grams) of kh2po4 in 250 mil and dose 15mil to get 1.37ppm per dose. 4.11per week

Aquarium calculators says to (mix 15 grams) of kh2po4 in 250mil and dose 15 mil to get 1.368 ppm per dose. 4.104per week.
This is a big difference in the amount to mix here.
Which is right??

Rotala doesn't have K2SO4 either. If I need to bump up the K

Next question:
What are my target levels per dose if I'm dosing 3 times a week
N, P, K, Mg, Fe

 

Thanks for the info, I did see the k2so4 on rotala, I don't know how I missed it, my bad.
I read an article on theplantedtank.co.uk that Tom Barr said to read and that site says to add per dose- N 8.1ppm, P 2ppm, K from N&P 5.93ppm, Fe 0.044ppm.
The Fe seems low on this. I was dosing .9ppm per week Fe The other numbers are close
Tom says to start off with high levels, should I bump up the numbers a little bit that you've listed above?

The only thing I don't get is why we need to mix so much MgSO4?

I really appreciate the help, thanks for taking time to help me.

 

Are the dosing numbers you gave me for a heavy plant load? My tank has a 50 to 60% plant mass. That's a combination of rooted and plants tied to rocks and drift wood.

 

That sounds good.. Thanks again for your help. Have a great weekend!!