Water flow for ray tank

[oakes]

Working on the water flow for my 300 gallon ray tank.
Currently just have one ray, about 6" disc diameter.
Do rays prefer more or less flow rate?
Right now I am running two FX 5's on it with regular water changes, might be adding a third in the very near future.
I do have some power heads I can add for added flow through out the tank just not sure if rays like slower moving water or a higher flow rate.
The tank is 8' long and 30" wide.

Any input is great! Thank!!

 

[MHDevelopments]

They prefer plenty of flow and need plenty of oxygen.
The added flow would also help to eliminate any 'dead' spots in the water column

 

[oakes]

Will be adding the power heads soon then.
I have two large sponge filters in the tank as well but will be adding another or at least a large air disc just for more oxygen into the tank.
Working on getting my air pump hooked up to PVC to better manage the air connections.

 

[MHDevelopments]

Let's have a full tank pic when you get time

 

[Daz123]

I always run my filter outlets just above warter level so it creates more oxygen in warter so I would say the more flow you can put in the better

 

[SandNukka15]

I also do the same and dont use air pumps

 

[oakes]

Full tank shot and pic of the ray.
Female Marble/Aparicio about 6" disc size.
I wasn't planning on getting the ray which is why I have sand in the tank now but debating on taking most of it out.
I need to get out 3 small and 1 large goldfish even though they are not bothering her but they produce a lot of waste! haha!

Both pictures taken tonight.