CETO water system render targets issue on iOS devices

I am trying to use CETO water system in my iOS game. When I run the build on iOS devices, I get following crash log:


Devices on which the build crashes: iPad Air (1st gen - A7 chipset), iPhone 6s (A9 chipset), iPhone 7 Plus (A10 Fusion)

Device on which the build runs properly: iPhone X (A11 Bionic)

Unity version: 2019.2.16f1

I have following questions:

1. Is this a limitation of CETO water system?
2. If no, how can I modify the code to make it run on majority of the iOS devices?

I would appreciate any suggestions and thoughts on this topic. Thank you.

 

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