>>>I will never need three at a time again
Now you've gone and done it.
No, you won't ever need three (carboys) at a time ... next time, you'll need FOUR carboys at the same time.
One can never have TOO MANY carboys.
Bite the bullet. Buy a three-gallon BETTER BOTTLE .... you'll thank me later.
I would also advise against putting three gallons of wine in a 5 gallon carboy UNLESS it's really early in the fermentation stages ... and even then, you are playing with fire ... ok, vinegar ...
My vote .... I think you should buy TWO more carboys. Call it a Christmas present to yourself. I guarantee you won't regret it.
>>never need three at a time again.
Thanks for the laugh. Remember, the goal is to "flood" the channel with lots and lots of wine ... it's the only way you'll ever have any wine get any "age" ... particularly if you have a wife like mine who ... well, never mind.