In general, epoxy sealers are the best paint to use for your boat. However, choosing a suitable epoxy sealer for plywood would be best. If you use the wrong epoxy sealer, then it may not be as durable and robust. Make sure you choose a good quality product so your boat will last longer. Some of the best epoxy sealers for plywood are: 1. Epifanes Clear Penetrating Epoxy Sealer – This is an excellent epoxy sealer that you can use for your boat. It has an outstanding reputation in the marine industry. 2. Interlux Brightside Polyurethane – This is another excellent epoxy sealer you can use for your boat. It has an excellent reputation in the marine industry. It is durable and robust so that it will last a long time. 3. West System 105 Epoxy Resin – This is another excellent epoxy sealer you can use for your boat. It has a very good reputation in the marine industry. It is easy to use and dries fast so that you can return to work immediately.