Use ships that have reclamation immunity where possible. This includes all starships, Neinzul Younglings, and Spire ships. Ships with very low caps are also usually immune.
Bulletproof fighters are immune to Shell ammo, which Leech Starships use.
Superweapons like Spirecraft, Golems, and Champions would all work, but I'm guessing you don't have those enabled.
Of the fleet ship types that are immune to reclamation, few have Heavy bonuses. Tigers have 2.4x, Shrikes 3x, and Reprocessors have a whopping 8x multiplier vs heavy, so those would all be very good for you. Reprocessors in particular are probably amazing since they have bonuses vs Heavy, Neutron, and Polycrystal, which covers most of the starships, excepting only Plasma Siege and Spire.
Spire Mini Rams don't have relevant bonuses, but they'd probably clear the field pretty fast.