| pain to use? You can buy AGA silicone in a caulk gun tube. Yes it is 2-3 times more expensive than good regular silicone but for all the other money that goes into your tank its worth the safety of the livestock.
I thought the gun was a little difficult to use in a tank, but you could try putting some into a plastic sandwich bag with a corner cut off and squeazing it out of that or some kind of cake decorator tool or a large syringe. That coudl make it easer to work with in tighter spaces, while still buying the larer volume discounted packaging. | 
