I use the one in the link. Yesterday I rode 70 miles and it was between 77-81 degrees. I took my filled 2L Camelbak (3/4 filled with ice), a 24 oz water bottle with homemade Gatorade, and 6 Fig Newtons (they work well for my tummy). The water is still cool (not cold) at the end of the ride. This Camelbak is super low profile. In terms of cleaning it, we simply rinse the bladder out, dry it with paper towels, the put a wooden spoon in it sideways to completely dry. This has worked well for the past three years. Here's the link:

https://www.sunandski.com/p/77530552...CABEgLfRvD_BwE