Got cpl of tips for ya!
Add a 1/2 cup Dolomite lime (powder) to 1 bag of OF and mix it in well.....Not surprised at your Ca/Mg problems. OF is light on that and the 1/2 per bag will fix the problem!
Just so you know.....Do not mix Epsom directly in soil......Mixed with water at around 1- 1 1/2 tsp and watered in, is ok.
Garden Gypsum,, good stuff, I love garden gypsum....Thing is, it's another one TO mix in the soil before use.....I'm afraid it won't do much worked into the surface...
I might throw in a bag of OF, something like this.
1/2 Cup Dolo
2 heaping Cups EWC
2 heaping Cups composted steer/cow manure
1.5 gallons coarse Perlite
1/2 cup Kelp meal
1/2 cup Alfalfa meal
1/4 cup Sumatran bat guano
Mix well and water. Cook for about 3-4 weeks and use......All you should be doing is watering this mix.....A little FF BB in bloom will not hurt at all.
The above mix adds myco's, aeration, and sufficient amounts of NPK to carry you to finish
