The photos you see are of a similar tool with vacuum & filter bag setup.
The process is: filtered water is discharged back in the ocean and the filtered captured material then is disposed of.

To capture and dispose of marine growth we recommend the following

• AS 18 with vacuum shroud assembly
• Tool can operate with or without vacuum
• 1.5" diameter vacuum hose attachment
• 1" hose is sufficient for vacuum a propeller
• Hose diameter of 1" with maximum length of 100 ft., length over 100 ft. will require 1.5" diameter hose up to 200 ft.
• You will require a gas or diesel water/trash pump, minimum of 8 HP

Attached is a photo of the discharge bag filter assembly

Filter bag is determined by micron size of debris

The most economical for your setup is to purchase tool with vacuum and filter bags

You can fabricate the filter bag support frame

Also, you can source the vacuum trash pump locally