This is how I tamed mine and you can prob do the same

What I used-

. Mastercraft crossbow+ stone arrows

. Full set of SCUBA gear plus extra SCUBA tank

. Extraordinary kibble (I had a bunch and it gives same effectiveness as exceptional kibble when taming basilo)

. My lvl 141 sarco with levels pumped into damage and health

How I did it

Found a high level basilo, swam up to it, and hit one of the mantas near by. Once I did all of the mantas went aggro and followed me on my sarco. Once I killed then all I swam up to basilo and fed kibble. After that I waited for it to get hungry again and while I did I killed some more mantas/megs that were swimming near by. I’m not taking any chances. Once it was hungry again i fed it until it was tamed.

Also, when using kibble, if you feed a creature any rarity of kibble that is above its preferred kibble it will have the same effectiveness. I used extraordinary kibble when taming my basilo, and basilos prefer exceptional kibble so it did the same thing. Sorry if it was confusing but I hope this helps. Happy taming!