Holding tanks

Hello folks. I’m the new owner of Athena in Portland. She’s my first trawler after five sailboats. She comes to me in pretty good structural condition having been either boathouse kept or stored under cover for most of her life but she will need a refit before the next season. It’s the usual stuff: weak batteries, none of her pumps work, The frig isn’t cooling and the hot water heater wasn’t heating. Shore power receptacle wired wrong. Most of that is either finished or in process. Engines and transmissions run and shift well.

She comes to me with a Mansfield TDX sanitation system that is a bit quaint. The treatment solutions needed are formaldehyde-based and that’s not doing the environment any favors. I’d like to install a conventional holding system. What has commonly been done to fit one. Perhaps I’m assuming too much but I assume the Bluewater 40 was drawn and produced without waste holding.

I’m wondering where to install the deck plate for pump out. I have not found a location that I’m all that excited about. Have any of you converted the shower tank? Athena has a big stainless tank in the forward bilge used to collect shower water with a transfer pump and an above water through-hull. Stainless is not the best material for waste water holding so I’m more likely to install a PE holding tank in the hanging locker just aft of the port head if I can find a way to route a hose up to a deck plate.

I’d love to hear of different and better ideas.

Thanks

Welcome aboard and congrats on your new boat.

I am not familiar with that particular boat but I will make a couple of recommendations. First I would go with a Raritan Marine Elegance head. It is an awesome head. I have put them in 4 boats now and have been extremely pleased with them. One thing I love is that you can use either 1” or 1.5” discharge hose. They come in multiple sizes and you can get elongated ones.

I would only use Raritan SaniFlex hose for discharge. It is extremely flexible and has a warranty against permeation. Defender sells it by the foot.

Ronco makes an excellent holding tank. They are heavy wall and they will install the needed fittings where you specify. They have hundreds of stock tanks.

Thanks Comodave. I have read about the Marine Elegance head. It comes well recommended. I’ve not investigated the Ronco tanks. I will do so.

I have put the Ronco tanks in 3 boats and they were well made.

Our current boat has a very long discharge hose, 36’. I used 1” hose for several reasons. One reason was that I ran it through the old 1.5” hose so it was simple and easy to run it. Second is that a 1” hose that long will hold a bit more than a gallon. A 1.5” hose holds about 3 gallons. So it takes a lot less water to flush the hose clean after use. The ME head has an optional smart control panel that you can program the length of flushes. It can flush without any water being added, fill, short flush or regular flush. If you are concerned about saving room in the holding tank then these options certainly help.

Athena currently has Electra Magic model 80 (Thetford) toilets. They have their own internal holding and “treatment”. One fills the toilet part way with water and adds a treatment solution. The bad thing is the treated waste is recirculated and used for flushing. I’d imagine it gets a bit disgusting over time. I do not know if these qualify as a Type I or type II MSD.

Esteemed TF member, author, and expert in all matters head related "The Headmistress" (Peggie), will know and will likely respond after seeing the thread.

Dcmeigs said:

I’ve not investigated the Ronco tanks. I will do so.

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Yep, Ronco tanks. They add fittings once you decide where they need to be.

And then see posts by Peggie.

-Chris

It seems like all bluewater 40s are different in layout and equipment.
Mine has a holding tank on centerline in the bilge and just forward of the stairs from the salon to down below. Each head has its own fitting into the tank. The deck pumpout fitting is about three feet forward of the port side fuel fill. The pumpout plumbing is regular black plastic pipe like you’d see in a house, and joined with short pieces of saniflex at the tank and pumpout fitting.
I would have done it a bit differently, and someday I’d like to install a larger tank and reconfigure the plumbing to be a bit neater.
My tank size is limited by the large house bank running down the bilge centerline. Someday when I need to switch the batteries, I’ll change to lfp batteries and save some room. That would allow a bigger tank.

Bmarler said:

It seems like all bluewater 40s are different in layout and equipment.
Mine has a holding tank on centerline in the bilge and just forward of the stairs from the salon to down below. Each head has its own fitting into the tank. The deck pumpout fitting is about three feet forward of the port side fuel fill. The pumpout plumbing is regular black plastic pipe like you’d see in a house, and joined with short pieces of saniflex at the tank and pumpout fitting.
I would have done it a bit differently, and someday I’d like to install a larger tank and reconfigure the plumbing to be a bit neater.
My tank size is limited by the large house bank running down the bilge centerline. Someday when I need to switch the batteries, I’ll change to lfp batteries and save some room. That would allow a bigger tan

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Good to hear from you. Is your holding tank stainless steel? Where does your shower drain?

Holding tank is plastic. Don't use stainless, it'll corrode.
Shower drain goes directly to a whale gulper pump and overboard via the sink drain.

Interesting. I’ll post a photo of my shower tank later. It’s ridiculously huge, I’d guess well over 15 gallons. As mentioned it’s in the forward bilge. Your pump out fitting must be near the wheelhouse door if I’m reading your post correctly. That’s just above the hanging locker where I propose to install the holding tank. Hose routing would be reasonably simple.

I'm sure the Elegance is an awesome head, but I chose the older Sea Era model because the service points are all right there, completely visible, and easily accessible for maintenance. Our newest one replaced an enclosed model that looks like Jabsco's version of the Elegance. It looked nice, but required removal to access the macerator and joker valve. I'll gladly trade seeing the mechanism for serviceability.

Good suggestions so far.
One I will add would be to plan & install a Bubbling system as part of your initial install.
Generally easier than as an afterthought when you encounter smells.

If convenient and reasonable distance, I have found my rerouted tank vent to the bow area to be advantageous... far from our and neighbors living space and ventilation paths if it does smell when flushed.
My Bacchus website - Projects section - has an article about holding tank aeration and my pump has been far more durable than I ever expected...10+ trouble free seasons of 24/7 operation. Total system ~$50 to install.

Dcmeigs said:

I’ll post a photo of my shower tank later. It’s ridiculously huge, I’d guess well over 15 gallons. As mentioned it’s in the forward bilge.

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Makes me wonder if the original intent was that the 15 gallon tank was a holding tank? And that it was subsequently re-plumbed/re-purposed for the shower drain. But the absence of a pumpout fitting makes that all seem less likely.

Speaking of that pumpout fitting... Ours is actually on the hull, about 18 inches down from deck level. At first I thought it was a strange place to put it. Then after witnessing and hearing about pumpout "accidents" whereby a bunch of nasty, stinky brown stuff spewed all over people's decks, I realized it was placed in a smart location. IF we have an accident, any crap would go right down into the water.

Dcmeigs said:

Interesting. I’ll post a photo of my shower tank later. It’s ridiculously huge, I’d guess well over 15 gallons. As mentioned it’s in the forward bilge. Your pump out fitting must be near the wheelhouse door if I’m reading your post correctly. That’s just above the hanging locker where I propose to install the holding tank. Hose routing would be reasonably simple.

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No, the deck fitting is right outside the galley window. The pipe actually goes through the galley cabinetry where the sink is.
Since all of the blue waters I’ve seen are different, the galley sink may be in a different location than mine.
You might want to post a couple of pictures of the boat sometime, love to see it. It’s not the one with the walk around decks is it?

Moonfish said:

Makes me wonder if the original intent was that the 15 gallon tank was a holding tank? And that it was subsequently re-plumbed/re-purposed for the shower drain. But the absence of a pumpout fitting makes that all seem less likely.

Speaking of that pumpout fitting... Ours is actually on the hull, about 18 inches down from deck level. At first I thought it was a strange place to put it. Then after witnessing and hearing about pumpout "accidents" whereby a bunch of nasty, stinky brown stuff spewed all over people's decks, I realized it was placed in a smart location. IF we have an accident, any crap would go right down into the water.

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I would like it if the pump fitting was about 12" before the deck level instead of on the deck. I've never seen that done.

Good evening, Domeigs...I didn't see this thread till now. You've certainly received some interesting replies and advice, much of which puts the cart ahead of the horse, 'cuz we need to sort out which toilet and what size holding tank makes the most sense for your use and the best place to put them before we get into the weeds of hoses and where to put a pumpout fitting.

So I have a few questions that need answers before I can offer any advice...starting with: how old is the boat? That the TDX device has a Mansfield label tells me it's late '70s-early '80s...and to wonder what the Thetford recirculating toilet replaced (and when)...and where in the boat it's located?

Let's start with the answers to those questions plus any that you have and we'll go from there.

And btw...Welcome aboard the Trawler forum!

--Peggie

I removed the SS tank in the bilge forward of the stairs to saloon and installed a Ronco 40 gallon holding tank. The tank has two 1" vents, one on each side and two outlets, one for deck pump out and one for macerator. The deck pump out fitting is on the port side deck, just aft of the rear of the Portugese.

I use a Gobius C tank level monitor, mounted on the outside of the top surface.

I am a dealer for both Gobius C and Ronco tanks.

I use a Gobius to monitor my water tank. It’s been very reliable.

tiltrider1 said:

I use a Gobius to monitor my water tank. It’s been very reliable.

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I've been very happy with my Gobius C. Measures 0 to 100% level from the exterior top of the holding tank without steps. Can view level from phone, tablet, NEMA, or other gauges. I use a WEMA level gauge in addition to my phone.

I had SCAD and Dometic level sensors in the past and the ability to view levels on a phone is a game changer.

Gobius C can also be mounted on water and fuel tanks

Disclosure, I am a Gobius dealer.