My 34 has an older Raritan Lectrasan (now called Electroscan) unit operating on sea water. Apart from replacing the electric grids once in 25 years it has been bulletproof.
Since seawater is the fluid, there is no need to add salt as in a fresh water lake. However, on a few occasions, in a marina or near a river outlet, a fresh water mix may see the salinity level drop below the required amount and the unit will automatically not allow flushing the toilet (it assumes you are not 3 miles offshore!). So even if you are diverted to the holding tank, it's won't operate.
A good unit.
Since seawater is the fluid, there is no need to add salt as in a fresh water lake. However, on a few occasions, in a marina or near a river outlet, a fresh water mix may see the salinity level drop below the required amount and the unit will automatically not allow flushing the toilet (it assumes you are not 3 miles offshore!). So even if you are diverted to the holding tank, it's won't operate.
A good unit.