RID-X in boat holding tank

My houseboat has a 40 gallon holding tank for “black water”, that is only for the waste from two toilets. We are always connected to a pump-out system that takes the effluent from the holding tank into the municipal sewer system. We normally need to pump out once every 2-3 days.

Some of our neighbors say that we should treat the holding tank with Rid-X once a month. Others say that it isn’t necessary.

Does anyone here have an evidence-based opinion about this?

Will be appreciated.

In this related threadthe efficacy of Rid-X in any circumstance is questioned.