Justin,

I have mine in a mix of peat and rose soil, top dressed with 2" of cow manure compost and she is three years strong (changed her mix this year and shes looking really happy)

Happy Citrus!

If you browse the forum or do a forum search on "potting mix" "gritty mix" or "drainage", you will find complete diatribes on the topic LOL.
There are a million posts here regarding potting media- literally chapters have been written on the very question you are asking.
Click the link below- I've run the first search for you (for free!) and the results will help you decide which mix to opt for.

Here is a link that might be useful: Potting mixes

I would not use the gritty mix. Besides the cost for 38 + gallons the weight alone would break your back. I would either use Al's 5.1.1 or or a good bagged mix like Fafards "heavy weight" mixes. You might get away with good ole miracle grow with added perlite.

Mike

I guess I should've mentioned that I have 26 of these containers so price will be a issue. I will go ahead and go through the forum and see what I can find and look at the various methods
Thanks everyone
Justin

Justin: Very ipmortant

I think an even more important thing you should learn is the concept of growing in the confines of a container and how container soils work in relation to water movement.

Once you learn this concept, then you will choose what mix best works for you and especially your trees:-)

Enjoy

Mike

Here is a link that might be useful: Container soils-Water movement