Holding tank upgrade

I have a 5 gallon plastic holding tank in the port side of my chain locker on Dulcinea Hull #66. I want to upgrand to a larger tank that can be pumped out at the marina. The current 5 gallons is obviously way too small and requires me to lift it out and carry it to the marina toilet to dump it out. What is the best solution to this problem. What would be the best tank solution? I would imaging I would need a pump fitting on the deck? Any guidance would be greatly appreciated.

John Curtiss
Dulcinea #66

John: Hi!

Sam L Morse Co has installed 16 gallon holding tanks in recent BCC28s. The specific tank used is from Ronco Plastics (a Californian company, based in Tustin; see http://www.roncoplastics.com) and is designated B125.

The tank is rotationally moulded from black heavy density linear polyethylene (the Ronco Plastics catalog, available from the company’s website, has dimensions. If you look at Figure 1 from my Stability Information Book, you will see where the tank is installed).

The Ronco B125 tank has a Beckson screw-out cleaning/inspection plate and fittings for a ?? nylon-reinforced PVC vent hose, which runs to a thru-hull well above the waterline, and 1?? hoses for fill and disposal.

Zygote’s holding tank has never been pumped out to shore (in Malaysia and Australia, the jurisdictions in which Zygote has spent most of her life, there are no or very few pump out facilities. Seems many municipal sewage companies do not like salty sewage), but she has a deck fitting for doing so. Your mileage in less salty water may vary.




Do you have a file server somewhere with all of the PFDs you’ve created? A few things lead me to think there is a storage space on slm.com for each boat’s forum user to put useful BCC files, but I don’t know how to access it. Either way, I’d like to look through your PFDs, so a link to their location would be great!

Thanks for the great references,


John, I would go with a Lectra-San unit and forget about all holding tanks and pump outs. They are expensive, about a grand U.S. $'s but make life very simple.

Thanks everyone for the great info. Stan, I looked at the Lectra-San unit. It looks like a great system. Apparently the Great Lakes have a zero discharge rule that prohibits even treated liquids from being discharged into the water. This came from my marina operator, so I’m assuming this is true. When I’m ready to cruise the ocean I will deffinately consider this system.

Does 18 hours seem a bit excessive for labor charges to install a new holding tank and deck fittings?

John, FYI, I took a slightly different approach to holding tank location. It was originally under the forecabin sole and I relocated it as high and far forward in the forepeak as possible (12 gallon tank). Anchor chain is now stored under the sole and the first thing we do when going offshore is to pump the holding tank over. I installed some valving to avoid accidental emptying of the tank and it has worked flawlessly for 7 years of full time cruising. Always nice to hear a new twist on an old theme, huh?