Fish only no live rock or inverts

I am planning on buying an intex pool as a pond for a Dasyatis sabina. It will be 1100 gallons. I am building a fiilter for it to provide adequate filtration and oxygenation. I can either keep him as a freshy with lots of water changes or I can keep him as marine. If it was marine I would have a protein skimmer. In fresh I wouldn't bother with the redundancy of a protein skimmer. If it was marine I would not put any live rock in for a few reasons
1. cost haha LR for something like that would be insane
2.probably not worth it
3.large scale aquaria for elasmobranchs I'm not wuite sure would need it

I have done all the research I can but I can not find anywhere that shows the setup of ponds for elasmobranchs that does not use LR.
Anyone know if its possible. I will most likely keep it fw then if it becomes too difficult and much more expensive.
All of this if I go to UC Merced instead of my other choices. So its only a possibility not a definite thing thats going to happen. Research research research I must before even starting the car to go buy the pond this summer or next year or the year after that.
Thanks for any links or info in adv.
Serafino

Is there even a point though for just a shark tank. Its not for decoration or to look nice its really for research I want to do and for a education program I want to start. I could make it but I don't really see a need to unless you can point one out for me. If its only for biofiltration I can do that other ways instead of using LR in the tank. I will probably have some LR in a refugium.