I designed a Wyze V2, V3, OG, V4 and Blink mini camera mount that can go on the outside of the tank. The mounts are 3D printed with PLA and have stainless steel hardware. The magnets used are capable of holding the camera on a tank with 1/2in thickness or less. The magnets are coated in plastic for the interior magnets making them reef safe. More @Wikipedia
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