Any downsides to a larger holding tank?

[DannyS]

Several years ago, I ripped out the toilet, hoses and tank on our new-to-us boat because everything was permeated and made the boat really foul. We've lived with a 5-6 gallon MSD since then and it has worked well since our marina does not have pumpout facilities. We are now moving to a new marina next that has pumpout facilities at every slip so we will be able to pumpout as much as we like for a fixed price of $60 for the year. The original tank was 13 gallons which I felt was a bit small for our boat. I'd like to go bigger but since we can pumpout every time we return home, we may not need to. The tank I've found to fit the space would be about 48" long, 8 1/2" wide and 12" tall. I think the original was about 28" long, 8 1/2" wide and 12" tall. So my question... is there any reason not to go bigger?

 

[Ed Schenck]

I think that converts to a little over 18 gallons, not too big and not too small. My tank is 22 gallons and with three big guys we could go three or four days before looking for a pumpout. My longtime procedure was to use as little water for flushing as possible during the day. Then at bedtime a good flush to clear the hose. As far as size if I could have gotten a 40 gallon tank in there I would have.

 

[Stu Jackson]

Think resale, too. The larger a tank, the further anyone else, even you, can go in the boat without pumpouts. Wouldn't that be nice?

 

[Bill Coxe]

Size matters, but so does access to whatever else is in the area. We installed an approx. 23g tank, an improvement over the original 15g, but there were problems fitting it through the access hatch and it REALLY restricted access to the overboard discharge valve. The advantages of having greater capacity in areas of limited pumpout facilities made the whole thing very worthwhile.

 

[DannyS]

Access is my biggest hurdle against going bigger. My tank will live under the v-berth and the access is narrow. I have two openings for storage under the v-berth that hold drop in pans. With the drop ins removed, the opening is approx. 10" wide and 24" long. I think I can get the 48" tank in without disturbing much. That one will give me an 18 gallon tank. Another option could get me up to a 25 -30 gallon tank. The two storage openings are on each side of the v-berth and I've toyed with the idea of cutting across the v-berth from opening to opening to make one large hole. That way I could build a cradle for a much larger tank, do the install, then replace the opening glass that I cut. I'd probably glass in some stringers under the v-berth to strengthen the berth and make the opening a permanent access port.
So this is my debate. Live with a smaller tank, and more frequent pumpouts knowing I have the ability to pumpout at our slip anytime I want, or go bigger knowing I can travel farther/longer but have a more involved installation.

 

[Peggie Hall HeadMistress]

Welll...look at it this way...

You'll only have to deal with the more involved installation once. Pumpouts never end.

 

[Geoff K]

Kracor in Milwaukee (http://www.kracor.com/) has tanks of innumerable shapes. They keep the molds from their OME work for many years. You might find a tank that fits the contours of your storage space closely and thus increases your volume. They made the tanks in my '79 Pearson and still have the molds for them. I didn't need a new tank but they gave me advice when I converted my bow water tank to a holding tank.

Geoff