From that day on, the area where water collects in a boat has been referred to as the bilge. You can get bilge cleaner in most marine hardware stores, however, it can be expensive. Liquid Tide is less expensive and does as good a job. Containing no phosphorus, being biodegradable, cutting grease and dirt and having a clean smell make it a good choice. However, if you are going to be using a large amount of cleanser, or if you will be discharging the cleanser into the water, choose an alternative from this list of Natural Cleaning Product Alternatives .
Some boats take in more water than others.
However, if you find an unusual amount of water make sure that you don't have a leaking through-hull fitting or pipe. If your boat usually has some water in the bilge just add the liquid Tide to the bilge and let the rocking of the boat do the cleaning for you. Most grease and dirt can be removed with Tide and perhaps a little elbow grease. However, steam cleaning can be an alternative. Steam cleaning is a harsh method that can cause paint to peel, especially on a wooden boat.