>>>>It is best to keep snakes separate. Especially different species.
Yes, a lot of people do, and have, kept snakes together but there is no true benefit to it.
There are definite drawbacks, though.
If one becomes sick there is a very good likelihood the other one will get sick as well.
It may also take a while (usually too long) to determine which one is the sick one.
If one regurgitates its food you won't know which one unless you happen to get lucky and see it.
If one has a problem stool you won't know which one.
Although a slight possibility, it has happened, one could eat the other. The smell of a prey item could trigger one snake to eat the other.
Like I said, this doesn't happen often but it has happened and is a possibility.
One or both of the snakes could be stressed by the presence of the other. Stress can cause a drop in appetite and lead to other health problems as well.
People will put multiple snakes in an enclosure and ask why one isn't eating.
When they are told it is probably due to stress caused by the other snake, the response is almost always "they like each other, they are always under the same hide together". Well this probably just means that hide or area of the tank has the optimum conditions they are looking for.
Snakes do not LIKE each other or ENJOY each other’s company.
So, in my opinion it is best to house them separate.
There are many reasons to keep them separate but no GOOD reasons to house them together.
I have usually found that when a person asks this question on the forum they have already made up their mind.
So, if you decide to keep them together, watch them closely. Keep detailed records. Lack of appetite and problem sheds can both be signs of stress, as can regurgitation.
If you see any signs of stress separate the snakes.
Also, be sure to feed them in separate containers and give them time to settle their feeding urge before placing them back together.

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Corn snakes and rat snakes..No one can have just one.
"resistance is futile"
Jimmy (draybar)

Draybars Snakes