Recomendations for clear resin or epoxy?

[Zombie Killer]

Anyone know of a good clear resin or epoxy that is forgiving in the bubble area and that does not get hot while curing? I want to put it in clear acrylic tubes to simulate liquid. I tried some of smooth ons 325 but it gets so hot is causes stress cracking in cast acrylic. Also as it cools it shrinks so once cures it is smaller then the tube and just comes out of the tube.

I tried it in this tube and it ends up with a million hairline stress cracks.

 

[robn1]

This stuff for floral arrangements looks pretty good, though I haven't tried it myself yet.

Acrylic Water | Hobby Lobby | 519306

Give faux flower arrangements a lifelike impression with a clear finish using this Acrylic Water. This two-part, clear, hard-setting gel sets over the course of two days after you pour it. Once finished, it'll look like your floral design is emerging from crystal-clear water. Make your floral...

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