What geotextile to use for pond conduit

We're building two 50 sq. ft. ponds with a 13ft dam for each. There is a high clay content so the pond and dam will be earth. The outlet conduit pipe acts as the primary spillway (control valve) and goes through the dam at a slight angle down slope. The pipe is 6 inch C900 (class 200 DR14) pvc pipe. We'll paint a coat of hydraulic cement onto the pipe and then quickly wrap the geotextile around the pipe and paint another coat of the cement on top of the geotextile. The purpose is to create a variegated surface in order to prevent water seepage along the pipe. Then we'll tamp clay around the pipe.

What type of geotextile would you all recommend I get based on this information?