If your Universal engine panel looks like this, and has an ammeter, you are due for some wiring fixes.
The factory wiring, with an ammeter in the panel, is flat out dangerous and this really needs to be addressed if it has not yet. It amazes me how many boats are out there still using this unsafe set up.
If you have an ammeter in your panel REMOVE it and jump your alternator 6" over to the starter post with heavy wire. Another alternative is to run your alternator direct to the house bank with a fuse or breaker within 7" of the battery and then add a combining relay or Echo Charger.
I have also measured voltage drops of 1.2+ volts or more at just 10A of charge current through these circuits. That means your alt is putting out 14.2V+ and the battery is seeing just 13.0 volts and is being chronically under charged.