Question
Hi, i have a few questions for you about growing aloe Vera plants(Some you may not be able to answer)  What kind of soil do they need?  When do i know when to water them? Why are they losing thickness in there leaves(leaves are curling inward)  

Answer
Brian,

What kind of soil do they need?  Usually typical "cactus mix" type soil is perfect. Whatever it is, it needs to drain well.

When do i know when to water them? Only when the soil is dry. Water thoroughly so that the soil is wet, then let dry out between waterings.

Why are they losing thickness in there leaves(leaves are curling inward) That will depend on a few factors. The type of Aloe (species), watering (too little) or root damage.

Some people assume that a tablespoon of water once a month is enough, but its not. Hope this helps!

Sincerely,

Greg