What could be causing that?
First of all none will have any idea what you should be dosing.
No idea of how much plant mass is in the tank.
More details would help many to answer.
If I had to guess you are starving your plants.
Propel dosed as written on bottle intends to keep .10ppm Fe in the water column.
This could be acceptable.
Synthesis provides a nitrogen source.
Dosed as labeled is equivalent to 1ppm of nitrate.
Many keep @ least 20ppm NO3 in the water column @ all times.
Envy, while being a clever name, I guess?
Is most likely a "Snake Oil" product that Seachem's marketing team has dreamed up.
Guaranteed analysis looks like a food additive.
Ascorbic Acid (Vitamin C) 2.5 mg
Thiamine (B1) 20 µg
Riboflavin (B2) 20 µg
Niacin (B3) 120 µg
Choline (B4) 4 µg
Pantothenate (B5) 70 µg
Vitamin B 120.8 µg
Inositol 10 µg
Arginine 300 µg
Glutamate 600 µg
Lysine 300 µg
Tyrosine 190 µg
Polyunsaturated Fatty Acids 600 µg
Phosphate, potassium, and many trace elements are missing from this dosing.
The hardness and alkalinity of your water also has elements to be considered.
Calcium and magnesium being the top two.
Regarding Parrot Feather:
Nice plant in a high tech tank but a quick grower.
Bronze/brown colors on top closest to the light.
This pic is older and from cut short stems, typically more brown on top.