As others have said, there's not really one good set of abilities to use with the Tentatek - it's a versatile weapon, and the gamemode and your preferred playstyle will be the key factors.
I tend to balance abilities around mobility and specials: Like other shooters, the Tentatek allows you to be highly mobile, since you can quickly create and swim through ink pathways, and so you're playing to one of its strengths if you boost your swim speed; likewise, with one of (if not the) highest run-speed while firing, run speed boosts enable you to utilise this to greater effect. Special charge up, special saver, and tenacity are all worthy of a slot (I tend to combine a charge with a saver), since anything which enables you to whip the Zooka out more quickly is a good thing.
If you use suction bombs a lot, ink saver sub is also worth considering, since you'll be less likely to be caught with an empty tank after throwing one.
It's pretty ink-efficient, so I find ink saver main/recovery are inessential, and damage up (single main) is somewhat redundant, since a single main defence up doesn't raise the Tentatek's shots-to-splat.