I keep syno decourus cats and armored (ripshaw) catfish in my pond and two syno decourus cats in my 120 as left over clean up crews. Dont bother the rays at all. Pretty laid back cats.
That said, I would be afraid to keep them all together at full grown size. My RTC was very feisty just before he moved out of the tank. Was even feistier in his 210g part time home. He jumped a week before moving into his pond. I was more afraid of him eating the dats than the rays though.
The RTC was probably around 18 inches or so. He was still a baby really, but had lots of room to spread out in the 450g. He also lived his whole life eating pellets and frozen foods. No live fish whatsoever.
He was fairly calm, but once he hit the 24" mark, I got nervous about him being in the tank.
Like other have stated, RTC and smaller rays are a no go. RTC just grow so fast that unless you already have big rays, they will over take the rays in growth and make a nice meal out of them.
The RTC was probably around 18 inches or so. He was still a baby really, but had lots of room to spread out in the 450g. He also lived his whole life eating pellets and frozen foods. No live fish whatsoever.
He was fairly calm, but once he hit the 24" mark, I got nervous about him being in the tank.