Bath help!!!!

Ok guys our current bath situation isnt working anymore. We have one of those tubs that sit in the sink and have a side for newborns and side for infants.

Hes out grown it.

So heres the issue. I cant use anything that goes IN the adult tub, as we have unremovable sliding doors in our apartment and i have bad knees that i cant lean over the tub with.

So...with that being said... do you have any tubs you recommend?

We also have another baby tub that he fits but he basically slides around in and floats. He could slip really easy. (Its the first tub without the newborn insert)

These are the two we have that dont work ⬇️