Best way to charge batteries

[Fej]

Hey guys.

My team has been having a big problem with dying batteries. I'll cut right to the chase - is there any benefit to charging the batteries more slowly?

We charge all of our batteries on the 6 amp setting. Even the one we got this year dies pretty quick. (They're all Genesis batteries)

We've ordered some more batteries, but we need to know if the charger is going to cause the same problem.