A giant ‘fish hotel’ has been submerged in an attempt to boost Murray River fish numbers.

The hotel - a three-metre stack of logs and concrete - is designed to help provide habitat for fish to breed.

The assemblage was dropped into part of the Murray river near Kingston-On-Murray, funded by local community groups brought together by local man Kym Manning.

“I know they work because I've had customers in our shop that have caught fish on the reefs that I put in the lake and they're about the tenth the size of this [structure],” Mr Manning has told the ABC.

“Funnily enough, I've had the Department of Environment ring me and they are going to try and do a similar project, but they're pretty keen to see how mine goes.”

Fish hotels mimick the original habitat of the river before it was cleared to allow paddle steamers through.

Mr Manning wants the state government to do more habitat restoration.

“Instead of all the money [from recreational fishers] going to the eastern states, it would be great to see people say; ‘Let’s go to South Australia, they've got the best fishing’,” he said.