Loon Outdoors makes three gel floatants:
Aquel: This premium gel floatant is the world's best fly floatant. Aquel is long lasting, silicon based and won't melt when it's hot or harden when it's cold. Furthermore, it masks human odor and won't leave any slick on even the calmest water. (Pronounced "ahh kwel")
Royal Gel: A gel floatant that adds a little shimmer to flies. It is silicone based and won't leave any slick on the surface, while adding an iridescent reflection that mimics clear wings.
Lochsa: Lochsa is a premium all-around gel floatant that even works on CDC. It won't mat dry flies made with CDC and is perfect for treating any type of feathers, hair, hackle, or yarn. Lochsa will provide maximum floatation without the slightest hindrance on appearance. It is silicon based, and won't melt in the heat or harden when it's cold.