Water tank recommendations

[CharmCityBoater]

I have two water tanks that I need to replace. They are both out of the boat. They were made from stainless steel. One was 35 gallons, the other about 45 gallons. Both have curves to match the location they were installed against the hull.

I would prefer to have them made from plastic; however, I have heard mixed opinions of custom made "plastic" water tanks that use plastic welding techniques. plastic rotomolded tanks seem fine, but the custom welded ones seem to suffer a lot from leaks. If I could buy one from Ronco that would fit I would. With that said I have searched through their long list and none are a good fit without sacrificing a lot of storage capacity.

Question:

1. If I were to go the custom plastic route whom would you guys recommend to build a custom plastic tank properly?

2. If I decided to stick with stainless, what company would you recommend to custom build a water tank based upon my current rusty / leaky tanks?

Thanks

Phil

[Cheechako]

Stainless does have it's problems, but can last quite a while. Were these in your Hans Christian? So they probably lasted 30-40 years?

I cant recommend a custom plastic maker but would go with plastic if you can. I had a very small tank made years ago of the welded variety, but it was just a rectangular tank for black water.
Definitely dont go with Aluminum for water tanks. You get this grey dripping sludge off the aluminum inside the tank! Don't use aluminum access covers either. You're drinking that.

If you go SS, often the problem area that corrodes is where the tank touches or is supported by something. It stays damp or wet there and the low oxygen result is where it corrodes.

[Kettlewell]

Another option is to utilize a bladder tank inside the old tank. I used Nauta water bladder tanks for years on a small cat we owned, and they never leaked.

[rslifkin]

And one more option that hasn't been mentioned would be to build a fiberglass tank. Either one shaped to install in the space, or one that's integral to the space where the tank goes.

[CharmCityBoater]

Yep, definitely ruled out aluminum. Not safe for drinking water. Bladder tanks work for those that have issues getting the old tanks out. Mine are out. I want a rigid replacement. Thanks for the suggestions.

Sounding more and more like I should stick with stainless. Between the inability to find a good custom plastic tank maker and the reports I hear of plastic welded tanks failing it seems inevitable. Now, if I could just find a good, reputable, stainless tank maker on the east coast between Baltimore and Miami.

Thanks

[CharmCityBoater]

Originally Posted by rslifkin

And one more option that hasn't been mentioned would be to build a fiberglass tank. Either one shaped to install in the space, or one that's integral to the space where the tank goes.

I had considered this. It is my understanding that to do it "right" is a pretty involved job. I would need to use food-grade FDA approved epoxy. Even then you can have issues if not done properly.

I was hoping to just pay someone to make one in the size I need. Simple pimple.

Thanks

[rslifkin]

Originally Posted by CharmCityBoater

I had considered this. It is my understanding that to do it "right" is a pretty involved job. I would need to use food-grade FDA approved epoxy. Even then you can have issues if not done properly.

I was hoping to just pay someone to make one in the size I need. Simple pimple.

Thanks

When I built one I built the tank with regular epoxy, then got a suitable drinking water approved epoxy coating (Aquatapoxy A61 in my case) and coated all of the interior surfaces with it. My water system has 2 decent size carbon filters in it as well, so that also helps with keeping anything that may leach out of the tank from ending up in drinking water.

[CharmCityBoater]

Originally Posted by rslifkin

When I built one I built the tank with regular epoxy, then got a suitable drinking water approved epoxy coating (Aquatapoxy A61 in my case) and coated all of the interior surfaces with it. My water system has 2 decent size carbon filters in it as well, so that also helps with keeping anything that may leach out of the tank from ending up in drinking water.

They would be in the bilge. I would need a way for the bilge water forward of the tanks to still drain aft of it. Would I just build a 1" to 2" channel at the bottom of the tank that water can still pass through? Having a separate bilge system for the forward bilge is not something I want to do.

[deblen]

No experience with these folk https://www.unitedplastic.com/


https://tidemanboats.com/

[rslifkin]

Originally Posted by CharmCityBoater

They would be in the bilge. I would need a way for the bilge water forward of the tanks to still drain aft of it. Would I just build a 1" to 2" channel at the bottom of the tank that water can still pass through? Having a separate bilge system for the forward bilge is not something I want to do.

That can definitely be done. When I built my tank in the center of the bilge area, I decked over the keel sump under it (powerboat) to allow water to pass under the tank. And I glassed in tubes to allow water from the limber holes on the stringers on either side of the tank to drain to the bilge under the tank (vs blocking off the limber holes by building over them). See the attached picture for an example of what I did.