Well, my recipe was something as follows for two gallons:
tree top juice
2 cansof concentrate
1 lb of brown sugar
WL Sweat Mead yeast
My starting gravity was 1.10.
On top of the tartness, there is a lot of alcohol burn as well. Interestingly, I have a friend who is big into whiskeys, and he came over and we started drinking my creation. Turned out that it grew on us. Could be that the more we drank, the more we didn't remember.
But actually, I kinda like it now. It definately has an unusual flavor profile, but that profile has a lot to like if you can get past the mouth pucker/alcohol burn. All that to say that I didn't try to fix it, as much as just understand it, and NEVER make it again.