I played a public on hard with this build not really planing on killing fruit that much.
It worked out pretty damn well.
Killed 320 on hard mode.
Build is simple
Get level 3 light fire and earth asap then get +2 pures so 4 total pures at end.
Place quarks on long path areas like center and entrance long path.
Place 4 lighting towers on center long path far right of it so they hit the far lane as well.
Use forge towers to amp the damage of everything by 120%
I dont get any money towers maybe you could if you wanted to.
I choose fire pures not sure if they are the best or not.
Quark towers are REALLY good in the early stages of the game if placed on long path areas in middle.
Be careful on earth waves early-mid mainly the spider one.
I bet if you got interest early instead of 2 pures at end you could kill quite a bit of fruit in very hard.
I might test it out later on.