We just bought a 1986 Monk 36. It was advertised as having a 30 gal. holding tank. The survey indicated a single 15 gal tank. Is there a way to find out the actual size of the holding tank?
Size of Aluminum Holding Tank
- Thread starter rusbet
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Take outside dimensions of the tank. Subtract two estimated thicknesses of the tank wall for each of the 3 Dims. (Ht. - Lgth. - Wdth.). Multiply all 3 dims together to get Cubic Inches of tank insides. Then devide by 231 Cu. In. per Gal. and that gives you the Max Gals. of that tank. Dick, S/V Puffin
Re: Size of Holding Tank
Of course, that's based on a rectangular tank (L x W x H, in inches), divided by 231 will give you the gallon capacity of the tank. But if it's an odd-shaped tank, it becomes a lot more difficult to figure out the gallon capacity. Many of the builders use Ronco tanks, and they put the mold number somewhere on the tank, in black Magic Marker. It would be a number like B131 - I can cross-reference the number to a gallon capacity for that particular tank (but only if it's a Ronco tank...) As an example, the B131 is a 15 gallon tank.
Ooops, you said an aluminum tank - Ronco only makes plastic tanks; my bad! But if it is rectangular, the L x W x H in inches, will still apply.
Of course, that's based on a rectangular tank (L x W x H, in inches), divided by 231 will give you the gallon capacity of the tank. But if it's an odd-shaped tank, it becomes a lot more difficult to figure out the gallon capacity. Many of the builders use Ronco tanks, and they put the mold number somewhere on the tank, in black Magic Marker. It would be a number like B131 - I can cross-reference the number to a gallon capacity for that particular tank (but only if it's a Ronco tank...) As an example, the B131 is a 15 gallon tank.
Ooops, you said an aluminum tank - Ronco only makes plastic tanks; my bad! But if it is rectangular, the L x W x H in inches, will still apply.
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Tank capacity
I find it helpful to be able to divide the tank into geometric volumes ie a triangular section and a rectangular section. The volume of the triangular section is 1/2 x length x width x depth then add the LxWxH of the rectangular section
I find it helpful to be able to divide the tank into geometric volumes ie a triangular section and a rectangular section. The volume of the triangular section is 1/2 x length x width x depth then add the LxWxH of the rectangular section
Never mind what size it is...
If the holding tank is aluminum, you'd be smart to replace it with a good quality plastic tank because urine turns metal tanks--aluminum and even 316 ss-- into colanders in a remarkably short time.
For more information on this subject, spend some time reading the discussions in the HeadMistress forum.
If the holding tank is aluminum, you'd be smart to replace it with a good quality plastic tank because urine turns metal tanks--aluminum and even 316 ss-- into colanders in a remarkably short time.
For more information on this subject, spend some time reading the discussions in the HeadMistress forum.
Peggy, we have ordered your book and look forward to getting it. In the meantime, this is what we have and what we need to decide:
Our holding tank is stainless steel not aluminum and it is 30 gal.
Our two Jabsco manual toilets do not work well (according to the survey) and are positioned more than 6 feet apart. Next April we plan to start the great loop from Naples, FL and to do it over 3 years or so. Most of the time will be in the Great Lakes area.
1. Does an ElectraScan make sense in our situation?
2. If yes, what is the recommended configuation. One recommendation we had was to hook the ElectraScan to the aft head, and to hook the forward head to the holding tank. If we are in NDZ for lengthy periods, we would then be liimited to using one toilet?
3. Do manual toilets work well with ElectraScan? We probably will just replace the manual toilets rather than fuss with service kits.
Our holding tank is stainless steel not aluminum and it is 30 gal.
Our two Jabsco manual toilets do not work well (according to the survey) and are positioned more than 6 feet apart. Next April we plan to start the great loop from Naples, FL and to do it over 3 years or so. Most of the time will be in the Great Lakes area.
1. Does an ElectraScan make sense in our situation?
2. If yes, what is the recommended configuation. One recommendation we had was to hook the ElectraScan to the aft head, and to hook the forward head to the holding tank. If we are in NDZ for lengthy periods, we would then be liimited to using one toilet?
3. Do manual toilets work well with ElectraScan? We probably will just replace the manual toilets rather than fuss with service kits.
Some suggestions, questions and answers
And btw, if we decide that a treatment device does make sense after all, based on what you've said so far, IMO a PuraSan--which is designed for use in fresh water, but also works in salt water--would be a better choice for you than the Electro Scan. Check it out here: Raritan Purasan
Stainless is just as vulnerable to urine as aluminum...it just takes a little longer. So you will have to replace it... the only question is whether it should be done now or can you wait. Do you know how old it is...when it was installed?
Replace 'em. For only a little more than the price of a Jabsco, you can upgrade to PHC "conversions"...check that out here: sbo.com PHII PHC LBA
You wouldn't be able to use in the Great Lakes or Lake Champlain...they're all "no discharge"...holding tanks only. So while you'd be able to use it almost everywhere else, I don't think it's the best choice for you at this time. However, you did say "Great Lakes AREA"...and you would be able to use in the rivers...so let's not rule out an Electro Scan or PuraSan yet.
And btw, if we decide that a treatment device does make sense after all, based on what you've said so far, IMO a PuraSan--which is designed for use in fresh water, but also works in salt water--would be a better choice for you than the Electro Scan. Check it out here: Raritan Purasan
That sounds like a good plan.
Yes, you would. But that's not the worst thing that can happen to you.
Yep...when installed correctly, the Electro Scan and PuraSan work just fine with ANY toilet. Wiring is the critical issue.
Re: Some suggestions, questions and answers
We don't know the age of the tank or when it was was installed. The boatyard is recommending against replacing the tank saying it will be many hours and many dollars. The tank is in the center of the boat in the V.
Our navigational area will be mainly in the the Great Lakes over the next 2-3 years with the exception of slowing getting there and returning. From there we can see doing the down east loop (St. Lawrence, around the Gaspe), as well as the Bahamas. I couldn't find anything on-line as to what is required to operate the PuraSan in salt water.
We like the PHC conversion (from the existing Jabsco manual toilets). How do we go about finding out which one will work for us and what all is required?
We don't know the age of the tank or when it was was installed. The boatyard is recommending against replacing the tank saying it will be many hours and many dollars. The tank is in the center of the boat in the V.
Our navigational area will be mainly in the the Great Lakes over the next 2-3 years with the exception of slowing getting there and returning. From there we can see doing the down east loop (St. Lawrence, around the Gaspe), as well as the Bahamas. I couldn't find anything on-line as to what is required to operate the PuraSan in salt water.
We like the PHC conversion (from the existing Jabsco manual toilets). How do we go about finding out which one will work for us and what all is required?
Nothing special is required to operate the PuraSan in salt water...it doesn't matter whether the toilet uses fresh water or salt water...it works equally well in both. There's nothing to set up or change, even if you start out in salt water and go up a river into fresh. However, based on your plans, I don't think you'll be able to use a treatment device enough to justify the cost to install one.
About your tank: If you were staying put in your home waters, I'd be in favor of, "it ain't broke yet, so no need to fix it yet." But sooner or later it WILL need replacing...and you're about to take off for distant ports...you want to minimize the risk of needing repairs--especially expensive ones--at the hands of strangers who may or may not be unscrupulous....and your conversation so far indicates that you're not knowledgeable or experienced enough to know who is. Urine eats through metal tanks from the inside...damage isn't visible from the outside till the metal is eaten through...so unless the yard has some kind of magic device that lets 'em see the condition of the inside of your tank--amount of pitting, size and depth of pits and corrosion--I'd recommend replacing the tank with a good quality plastic one before you leave. It's a job that anyone with minimal mechanical ability can do yourself...if you don't have at least that much, you don't have enough to maintain a boat. Depending upon the age/condition/brand of the hoses, it may be smart to replace those too.
About the PHC/PH II conversion: they both use the same pump...one is on a "full size" base, the other is on a "compact" base...it's just a matter of which one you have enough space for. So take measurements and buy the one that fits.
About your tank: If you were staying put in your home waters, I'd be in favor of, "it ain't broke yet, so no need to fix it yet." But sooner or later it WILL need replacing...and you're about to take off for distant ports...you want to minimize the risk of needing repairs--especially expensive ones--at the hands of strangers who may or may not be unscrupulous....and your conversation so far indicates that you're not knowledgeable or experienced enough to know who is. Urine eats through metal tanks from the inside...damage isn't visible from the outside till the metal is eaten through...so unless the yard has some kind of magic device that lets 'em see the condition of the inside of your tank--amount of pitting, size and depth of pits and corrosion--I'd recommend replacing the tank with a good quality plastic one before you leave. It's a job that anyone with minimal mechanical ability can do yourself...if you don't have at least that much, you don't have enough to maintain a boat. Depending upon the age/condition/brand of the hoses, it may be smart to replace those too.
About the PHC/PH II conversion: they both use the same pump...one is on a "full size" base, the other is on a "compact" base...it's just a matter of which one you have enough space for. So take measurements and buy the one that fits.
"...you want to minimize the risk of needing repairs--especially expensive ones--at the hands of strangers who may or may not be unscrupulous....and your conversation so far indicates that you're not knowledgeable or experienced enough to know who is...."
Yup...you figured us out. I guess that's why we appreciate your candor.
We've been in touch with Ronco and they have been so helpful in identifying the couple of areas that we need to consider ie. the size of the trap door, and how secure the exisiting tank is installed. Talk about an education. They suggested we take photos, take measurements of the existing tank, draw a sketch with location of current fittings. They told us what to look for with respect to taking out the old tank but they did caution us that we needed to know if a new tank could be positioned in the space BEFORE we had any thoughts of removing the old tank.
So we will soon be off to look at our baby and see if a new tank can be installed without the services of a cabinet maker.
Yup...you figured us out. I guess that's why we appreciate your candor.
We've been in touch with Ronco and they have been so helpful in identifying the couple of areas that we need to consider ie. the size of the trap door, and how secure the exisiting tank is installed. Talk about an education. They suggested we take photos, take measurements of the existing tank, draw a sketch with location of current fittings. They told us what to look for with respect to taking out the old tank but they did caution us that we needed to know if a new tank could be positioned in the space BEFORE we had any thoughts of removing the old tank.
So we will soon be off to look at our baby and see if a new tank can be installed without the services of a cabinet maker.
We prob'ly oughta talk privately..'cuz the folks at Ronco are wonderful, but they're just tank mfrs...I know a WEE bit more about installing 'em on boats. So send me an email--NOT a PM please!--and I'll send you a phone number.
Peggy, could you advise the model #Raritan Elegance you recommend (around $600). I think we are going to bite the bullet and get either one electric and one manual, or two electrics. We checked the models on the Defender website and there are just too many choices. We understand that there are angled and straight models but aside from that there are still models that appear to be the same but have different model #'s and prices.
I just sent you an email.
There aren't really THAT many choices...it's a matter of which one fits your space.
There's a short version and a tall version...which one depends on whether your head sole (floor) is flat or the toilet sits on a raised platform...
Straight back or slanted depends on where it's gonna sit--against a straight bulkhead...or against a sloping hull....
The Elegance is designed to use pressurized flush water...but it can use sea water if a remote intake pump is added (extra cost)...
I'd have to check to see whether white or almond makes a difference in the price...
"Smart Flush" is an option that adds to the cost.
So...only you can decide whether you want a short or tall one, straight back or slanted, white or almond, fresh water or sea water and the smart flush or just a flush button. Once you get that sorted out, we'll figure out which one you need to order.
There aren't really THAT many choices...it's a matter of which one fits your space.
There's a short version and a tall version...which one depends on whether your head sole (floor) is flat or the toilet sits on a raised platform...
Straight back or slanted depends on where it's gonna sit--against a straight bulkhead...or against a sloping hull....
The Elegance is designed to use pressurized flush water...but it can use sea water if a remote intake pump is added (extra cost)...
I'd have to check to see whether white or almond makes a difference in the price...
"Smart Flush" is an option that adds to the cost.
So...only you can decide whether you want a short or tall one, straight back or slanted, white or almond, fresh water or sea water and the smart flush or just a flush button. Once you get that sorted out, we'll figure out which one you need to order.
Re: I just sent you an email.
Peggy, I feel so foolish. I looked at the video of the Raritan Elegance and then went to the Defender website and understood the choices. What are the determining factors between a decision for fresh water or sea water?
Peggy, I feel so foolish. I looked at the video of the Raritan Elegance and then went to the Defender website and understood the choices. What are the determining factors between a decision for fresh water or sea water?
No need to feel foolish...
For one thing, although the Elegance CAN use sea water by adding a remote intake pump (which adds considerably to the cost), it's actually designed to use pressurized fresh water...and it's much more efficient and MUCH quieter in that mode. Then there's the matter of sea water odor...and even fresh water can be "skanky." Toilets that use onboard fresh water eliminate that problem. So unless you have a real shortage of fresh water that doesn't provide any to spare for toilet flushing, there's every reason to go with the fresh water version and none that I can think of to go with a sea water intake pump.
For one thing, although the Elegance CAN use sea water by adding a remote intake pump (which adds considerably to the cost), it's actually designed to use pressurized fresh water...and it's much more efficient and MUCH quieter in that mode. Then there's the matter of sea water odor...and even fresh water can be "skanky." Toilets that use onboard fresh water eliminate that problem. So unless you have a real shortage of fresh water that doesn't provide any to spare for toilet flushing, there's every reason to go with the fresh water version and none that I can think of to go with a sea water intake pump.
Re: No need to feel foolish...
Hi Peggy,
We ended up purchasing two Raritan PHC. It became too complicated to go with the Elegance or Sea Era and dealing with the boatyard long distance. We needed functioning toilets to bring the boat home. We are happy that at least we will have well recognized toilets even if they are not electric.
So now I am trying to find out what cleaning products to use. Raritan has a number of different products. From forum searches, it seems we should get the KO & CH. Is there anything else you would recommend?
BTW, your book is still on back-order with Amazon.
Hi Peggy,
We ended up purchasing two Raritan PHC. It became too complicated to go with the Elegance or Sea Era and dealing with the boatyard long distance. We needed functioning toilets to bring the boat home. We are happy that at least we will have well recognized toilets even if they are not electric.
So now I am trying to find out what cleaning products to use. Raritan has a number of different products. From forum searches, it seems we should get the KO & CH. Is there anything else you would recommend?
BTW, your book is still on back-order with Amazon.
A good choice...
You definitely need Raritan C.P....prob'ly not C.H. though unless there's already a serious sea water mineral buildup in your hoses. And we should talk about your holding tank venting to determine whether K.O. or Odorlos is the best choice.
As for my book, kill the Amazon order (I dunno what's going on between them and my publisher) and order it from the online store at this site...just click on the link in my signature.
You're getting there...:dance:
You definitely need Raritan C.P....prob'ly not C.H. though unless there's already a serious sea water mineral buildup in your hoses. And we should talk about your holding tank venting to determine whether K.O. or Odorlos is the best choice.
As for my book, kill the Amazon order (I dunno what's going on between them and my publisher) and order it from the online store at this site...just click on the link in my signature.
You're getting there...:dance:
Re: A good choice...
We will see our boat again on Nov. 12 and then can provide information on the vent line for the holding talk. The book has been ordered at the online store on this site. A big thanks!
We will see our boat again on Nov. 12 and then can provide information on the vent line for the holding talk. The book has been ordered at the online store on this site. A big thanks!
Re: A good choice...
Peggy, the Raritan PHC's are working great. We just finished eights days on the water bringing our boat home. I could not find anything in the instruction manual regarding when to use the wet flush and when to use the dry flush, and how many pumps for either. It appears that the discharge from the toilets to the holding tanks goes direct without any loops (we are a trawler not a sailboat) if that makes any difference.
Peggy, the Raritan PHC's are working great. We just finished eights days on the water bringing our boat home. I could not find anything in the instruction manual regarding when to use the wet flush and when to use the dry flush, and how many pumps for either. It appears that the discharge from the toilets to the holding tanks goes direct without any loops (we are a trawler not a sailboat) if that makes any difference.
It depends...
I think you have my book...the section "Flushing Manual Toilets 101" in the chapter "Flush With Success" provides a detailed answer to your questions about how to use wet and dry flush.
As for the straight no-loop run to the tank...trawlers don't heel, so no loop is needed for a toilet that only flushes into a tank. One IS needed in any line that goes overboard...and that does include your toilet intake...although the line from the thru-hull to the pump is the wrong place to put that one. It needs to be installed between the pump and the bowl.
Glad you had a good "delivery" trip home!
I think you have my book...the section "Flushing Manual Toilets 101" in the chapter "Flush With Success" provides a detailed answer to your questions about how to use wet and dry flush.
As for the straight no-loop run to the tank...trawlers don't heel, so no loop is needed for a toilet that only flushes into a tank. One IS needed in any line that goes overboard...and that does include your toilet intake...although the line from the thru-hull to the pump is the wrong place to put that one. It needs to be installed between the pump and the bowl.
Glad you had a good "delivery" trip home!
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