Just out of curiosity,why so many "plugs". Why not just buy one filter that does it all instead of 3 and pay so much electric to run them? It would probably be cheaper(dont hold me to this) to just run and FX5 than 2-70's and a cannister.
And no,I am not suggesting he use an FX5 I am just using it as an example. (about electric used.)
I do know that in regards to flow rate you would get 100 more gph with 2 AC70's than 1 AC110 but it would still be enough for a temporary filter on that 40 that is going to need to be upgraded within a few moths time and then still be used on the new bigger tank that the OP will need anyway.
In any case,as I said before,just keep in mind that in the future you will need to upgrade and get a bigger tank and more filters again if you buy all small filters which is why you should look for a filter that you will be able to use on the bigger tank.