Holding tank construction

[Gene H]

Another project while the boat is laid up for the transmissions is a new and larger holding tank.
I'm somewhat accomplished fabricator so doing the job isn't the issue. What is the best material to build a holding tank out of? Fiberglass, aluminum or stainless steel? All other issues aside (weight, forming, shape, etc)?
The boat has a fiberglass tank now but if I had my choice, aluminum is so easy to work with and is almost as light. We're only talking about a 17" deep x 22" wide x 38 " long tank.
GH

[Lancerbye]

I recently aquired a Lancer 44 motor sailer which was very well maitained. The holding tank is unusual but practical and functional. It was made out of 2- 10in. i.d. White type PVC pipe each about 5 ft. long joined together and stacked one above the other with reducing Tees 10 x2 and the ends capped with PVC slip joint cap. This whole thing is made out of PVC pipe which is easy to plumb to because of the available fittings cheap. and glued together.You get 3.4 Imp. Gals per foot of pipe. Another type to consider.

[ted655]

Originally Posted by Gene H

Another project while the boat is laid up for the transmissions is a new and larger holding tank.
I'm somewhat accomplished fabricator so doing the job isn't the issue. What is the best material to build a holding tank out of? Fiberglass, aluminum or stainless steel? All other issues aside (weight, forming, shape, etc)?
The boat has a fiberglass tank now but if I had my choice, aluminum is so easy to work with and is almost as light. We're only talking about a 17" deep x 22" wide x 38 " long tank.
GH

We just had to replace our fresh water & holding tanks. They were aluminium. When tour fellow drove straight to the Gibson plant to get the new plastic tanks, he took the alums to show them the teeny pinholes. The yard forman didn't even look. He grunted in agreement & told our guy to pull behind a far building to duscard them. When he rounbded the corner he saw a MOUNTAIN of replaced aluminium tanks. Someday we may be drinking sodapop from these discards. Gibson is claining that chlorene is the culpert.
Just a firsthand experience with aluminium tanks. Good luck.

[Sean Herron]

Hello...

We have used these guys for all our primary tanks and sumps for tubs and showers - black and grey water - and freshwater - diesel remains welded aluminum...

These tanks are fantastic - throw them off your roof into the parking lot - fill them up and pressure test them beyond specs. and they just dont burst - best of all - no leaching of the inevitable '5 year stink'...

Shipping might cost a bit - you may have a local group doing same - get out your Yellow pages and start looking up Agricultural tank Mfgs'...

See http://www.barrplastics.com/plastic_fabrication.htm - pay the money and never think about it again ...

Cheers...

SH.