You can get a larger tank, or parallel two smaller tanks (requires two regulators), or put your tank in a tub of warm water (water is the last thing I want to have around a pour).
Perhaps an easier method would be to put a fan blowing on the tank to warm it.
My philosophy is:
1. Don't solve problems that you don't have. Use the most simple solution with the fewest parts, and if that works, then don't add complication just for the sake of doing it like someone else mentioned.
2. Find a base setup/arrangement that works, and then experiment after you get a working arrangement. Some people change too many variables too quickly, and it can be difficult to figure out cause and effect doing that sort of thing.
3. Some like to experiment and learn as they go. For me, I would rather look at a number of working systems, and then combine the best of all those systems into a hybrid design that works better than any individual design, or at least combines the good parts of a number of different designs.
I don't use additives, charcoal, crucible covers of any kind, stirring, etc.
What works for me is using clean aluminum only, melted as fast as possible, skim and pour.
Don't make it more complex than it has to be (is my philosophy).
There are methods that can be used for degassing aluminum, some very toxic, some expensive, but if you don't have gassing problems (I don't) then don't solve problems you don't have.
Just my approach; everyone has their own method to the madness (or should I say MadModderness).
