Filling water tank with concrete. General Forum Forums

I think you are creating problems for yourself or another owner in the future if you do this. I would suggest four possible alternatives that I think would be better.

1. just don't use it and ignore it.

2. get one of the epoxy sealers designed to fix leaks in tanks.. PPG has several products that would cover this situation. It would allow you to use your tank again.

3. Cut the exposed top under the hatch open and use it as extra storage space. I cutting blade on a grinding wheel would quickly open it up. 🙂 You could use the extra space for a second battery bank that is easier to access.

4. Cut the tank up into pieces and remove totally.

if you fill it with concrete it will make it  virtually impossible to ever do anything different with that space as it will be impossible to cut it up and remove it afterward. I also don't think that adding ballast on our boats is necessary. they are quite stiff as is and you can wait till about 25knots of wind to reef with all sail up, or maybe 18 to 20 knots if  your just doing comfortable sailing. If you intended to put a taller mast on her then I might change my mind about more ballast.