Howdy clv5464, and welcome aboard iRV2
You've gotten some good answers regarding keeping the coach plugged in and watching the battery water level.
There are two battery banks in your motorhome. One groupe is used for starting the engine and operating the chassis, the other group is known as the coach or house batteries and operate the 12 volt electrical loads inside the motorhome. Each battery bank may be a single battery, or one or more connected together depending on the motorhome builders design.
The trick-l-start is designed to keep a charge on the engine starting battery. That system is designed to keep a low current charge going into the battery so that if the motorhome isn't used for an extended periord of time, the engine battery will not be discharged. Normally, the trick-l-start will not overcharge the battery so you don't need to be as concerned with water useage in the engine battery.
The house batteries on the other hand do need to be checked for water consumption when you stay plugged in for extended periods of time. How often you must check and add water depends on what type of charger/converter your coach has. A typical converter that outputs a fixed voltage can tend to overcharge the batteries which will increase water useage. With that type of charger, I'd suggest checking the water at least monthly, and perhaps more often if you find the batteries needing water added. If you have a "charge wizard" or more advanced three stage charger on your motorhome, the charger will automatically reduce the charging voltage and amperage as the battery become charged. This will drastically reduce the water consumption and you will need to add very little.
In my case, I leave our motorhome plugged in all the time at home, and with the 3 stage charger I find I only add water once a year.
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Joe & Shelly, Justin, Tyler, Alyssa | Butler PA
2008 Tiffin Allegro Bus 43QRP|Cummins 425|Honda CRV