The easy way would be to just dose 1/2 or 1/3 EI levels for macros, 1/5 - 1/10 micros. This would probably be fine.
But if things are going well now and you dont want to mess with a good thing....
You can use a nutrient calculator to see how many ppms you are currently dosing, and dose the same amounts using dry ferts.
Rotala Butterfly | Planted Aquarium Nutrient Dosing Calculator
To figure the Flourish liquids, select "premixed" then the specific Flourish product from the drop dow menu.
Beside "I am calculating for" select the "result of my dose"
Beside "I am adding" enter however much of the product you are currently adding per dose.
This will tell how many ppms of each thing you are currently adding.
Then for dry ferts
"I am calculating for" -> "dose to reach a target"
For the target, enter the same ppm you are dosing now. It will tell you how much to use in dry ferts.
KNO3 = Flourish Nitrogen
K2PHO4 = Flourish Phosphorus
K2SO4 = Flourish Potassium
CSMB = Flourish Comprehensive (calculated for Fe)
*Note that KNO3 and K2PHO4 both provide some potassium as well. So when you calculate for K2SO4 (assuming you have this) subtract the amount already coming from the previous two compounds from your target ppm for K.
Hope that makes sense lol