Tongue Coral?

Are they as 'circular' as this one though? I thought they're more 'oval-ish'

So in the last 6 months, the lack of posting is a direct result of my flat worm infestation that I've been battling.

I've finally been able to get a local LFS to get in the flatworm eating nudibrachs, but they want $25/each for them.

I'm curious, how many flatworms does one think a nudibranch could eat in a day? I know I probably have close to 400-500 I can see so probably over 1000 realistically so I was trying to figure out how many to buy... I was thinking 3?

Recognizing that once the flatworm population in my tank disappears I will return the nudibranchs to the store so they can find food in someone elses tank!