Not without more information.
What kind of batteries do you have?
How are they connected together?
How many amp hours do you have in the bank?
Are any of them separated out for the engine? Isolated?
What is your usage?
How many amp hours do you draw between charges?
How quickly do you need to recharge?
For example:
I have 2 Marine Deep Cycle Group 31's connected together in parallel for a total of 210 amp hours in the bank. I have LED lights, fans and a radio. I will typically draw 30 aH during the day, and maybe 20 overnight. Usually, my maximum usage would be 2 days and 2 nights, so I have enough aH in the bank to get me through. I'll dock up Sunday night and return Friday night...unless I get a Wednesday evening in. I've got all week to charge.
I use
this Guest charger. It fits my needs and capacity.
Your needs may vary...depends on the answers to the questions above.