How to set max_filesize for clamav in docker-compose.yml

I'm trying to setup a docker container with clamav and am struggling to allow for larger files to be scanned. I've set up my docker-compose.yml like this:

version: "3.3"
services:
  clamav:
    image: clamav/clamav:latest
    environment:
      CLAMD_CONF_MaxFileSize: 250M
      CLAMD_CONF_MaxScanSize: 250M
    restart: always
    ports:
      - "3310:3310"

but that doesn't seem to do it (I keep getting a Broken Pipe Error). I presume I'm just using the wrong variables, but I can't seem to find the right ones.

Can anyone point me in the right direction?