To Tank or to Tank?

[Colin Stone]

Rubber bag tank inside existing tank shell?? I have 5800 litres in 4 rubber bag tanks which sit in plywood boxes. Drinking water is filtered through a Jabsco unit. Works well..

[Goodxcharly]

Plastic lasts for ever.

[siamese]

If you go with Ronco, you gotta see if they'll throw in a Pocket Fisherman!

[VChild]

Originally Posted by peghall

Metal water tanks that carry treated municipal water have an average lifespan of about 20 years, a bit less if you add a little bleach to each fill. So I agree that a plastic tank is best way to go.

Almost all off-the-shelf PE tanks have only 1/4" thick walls...all vertical walls would have to be externally supported to hold 55 gals of water or waste, both of which weigh 8.333lbs/gal, without flexing or bulging.

IMO Ronco Plastics is your best source. They make TOP quality thick-walled (50% thicker than most other mfrs) water and waste tanks for a very reasonable price and have more than 400 shapes and sizes, over 100 of which are non-rectangular, and they install fittings--including diptubes--in the sizes and locations specified by the customer when they make the tank. There are retailers who sell Ronco tanks, but Ronco sells direct for a much lower price...and they're great to work with.
Ronco Plastics marine Tanks Ronco Plastics tank drawings


--Peggie

If Ronco doesn’t have the shape you need, I highly recommend a company called Dura Weld in Lake Worth, FL. They fabricate custom plastic potable water tanks for boats in any shape you need. They are thick walled and internally baffled appropriately. They will integrate any fittings you need on any part of the tank. Mine both had custom tapers to fit the shape of the bilge. The company has a fast turnaround time. Gareth, the owner was very helpful and my tanks came out perfect. My old tanks were the original (1983) stainless steel tanks that came with the boat. They had developed severe crevice corrosion at the bottom edges and were leaky. Here are a few pictures of the project and tank design.

[s/v Jedi]

I recommend you check the Tally Ho video about water tanks, especially the custom shape plastic ones that he had to discard because they leaked more than a colander

[UFO]

Originally Posted by s/v Jedi

If you plan to use the water for consumption then use stainless steel or fiberglass with specialized coating inside, no plastic.

Even if you plan to filter, check if your filter can take out everything that a plastic tank can seep out. As long as one can taste it, something comes out.

Any ideas what those chemicals are and what filter system would do that?



Its quite easy to remove the taste, but its what lurks beneath that worries me, as plastics have a direct and negative effect on the body's endocrine system and god knows what else.


The Seagull system looks good, but finding out if it would remove such contaminants is not so simple. As far as I can tell RO systems are the best, but room under my sink is limited and running a Saltwater RO and then having to run another one for drinking water seems like overkill.

[VChild]

Originally Posted by s/v Jedi

I recommend you check the Tally Ho video about water tanks, especially the custom shape plastic ones that he had to discard because they leaked more than a colander

I don’t know about Tally Ho’s tank supplier but I can tell you Dura Weld is high quality. I was offshore in the Gulf of Mexico in extreme conditions with high winds and tall, short period waves. We were motoring slowly into the waves. It was dark and no moon so I couldn’t see the wave height but our 35,000 lb. Lord Nelson 41 was heaving the bow up to crazy heights going into each wave. The bow would then free fall off the wave and bury the 8ft bow pulpit and entire foredeck into the base of the next wave. We felt near weightlessness as the bow would come down off each wave. This went on for more than 6 hours before we made it into Tampa Bay. The new plastic water tanks were full during this beating. We inspected the entire vessel the next day including the tanks. The tanks were perfect. I figure if they could pass that stress test, they were good enough for me. I did look at the Tally Ho video as you suggested. Those tanks look pretty thin!

[dfelsent]

Originally Posted by UFO

Any ideas what those chemicals are and what filter system would do that?



Its quite easy to remove the taste, but its what lurks beneath that worries me, as plastics have a direct and negative effect on the body's endocrine system and god knows what else.


The Seagull system looks good, but finding out if it would remove such contaminants is not so simple. As far as I can tell RO systems are the best, but room under my sink is limited and running a Saltwater RO and then having to run another one for drinking water seems like overkill.

There are some excellent filter cartridges around these days. Not just Seagull.

https://www.freshwatersystems.com/pr...0-5-mic-filter

Fits in a big blue housing. Low pressure drop. High capacity.

[s/v Jedi]

Originally Posted by VChild

I don’t know about Tally Ho’s tank supplier but I can tell you Dura Weld is high quality. I was offshore in the Gulf of Mexico in extreme conditions with high winds and tall, short period waves. We were motoring slowly into the waves. It was dark and no moon so I couldn’t see the wave height but our 35,000 lb. Lord Nelson 41 was heaving the bow up to crazy heights going into each wave. The bow would then free fall off the wave and bury the 8ft bow pulpit and entire foredeck into the base of the next wave. We felt near weightlessness as the bow would come down off each wave. This went on for more than 6 hours before we made it into Tampa Bay. The new plastic water tanks were full during this beating. We inspected the entire vessel the next day including the tanks. The tanks were perfect. I figure if they could pass that stress test, they were good enough for me. I did look at the Tally Ho video as you suggested. Those tanks look pretty thin!

Yes but top rated company as I understood it. Theo is nice enough to not mention their name though.

Stainless steel simply rules for consumption water storage. Well glass as well but that’s a bad idea on a boat

[s/v Jedi]

Originally Posted by UFO

Any ideas what those chemicals are and what filter system would do that?

Its quite easy to remove the taste, but its what lurks beneath that worries me, as plastics have a direct and negative effect on the body's endocrine system and god knows what else.

The Seagull system looks good, but finding out if it would remove such contaminants is not so simple. As far as I can tell RO systems are the best, but room under my sink is limited and running a Saltwater RO and then having to run another one for drinking water seems like overkill.

Here is how I understand this: a rating for a filter is for one substance/bacteria only. If you want 10 things tested, you need to repeat this process for every item. As this is expensive, it’s not done.

Only very few materials have shown long term safety for water storage. From memory, so could be wrong, it is stainless steel, cement as used to coat inside of iron tanks, concrete cisterns etc. and just one or two special coatings that are compatible with fiberglass tanks.

All these plastics marketed as “BPA free” etc. have an expiration date like one year into using it. Many, like PET bottles are not to be reused at all.

[VChild]

If you have a very low turnover of water in an HDPE water tank and are concerned about endocrine disrupting compounds (nonylphenol and bisphenol A), I believe the correct water filter rating to use is the NSF/ANSI 401 rating. See picture.
As a side note, there is a weight penalty with stainless steel tanks versus plastic. Also of note, weld imperfections (not all visible) can cause very premature crevice corrosion and leaks, as can retained water in the bilge under the tank.

[Dirk01]

Originally Posted by s/v Jedi

I am afraid we live in a time where your health is not on the mind of those manufacturing and selling water tanks. You can not just “expect” you will be fine, you need to make sure. Like those “candle filters” so popular with offgrid living… there was no need for their independent test results… until someone paid to have it done and they failed big time.

Filters need official ratings and you must know what (incl. which chemicals) they are rated to block to levels safe for consumption. Many filters in use do not have those ratings.

I have done a lot of testing and the only time I can’t taste the chemicals coming from plastic is with a new polycarbonate bottle. When the bottle is a year old, I can taste it (and they have a due date printed on them).

My test is simple: take RO water, filter that through a NSF rated filter (like Seagull IV) then fill a stainless steel bottle, a glass bottle and the bottle (or tank) you test. Let it stand for 24 hours then do the taste test.

Most people can tell the difference between Coke from a plastic bottle or a glass bottle and this is why they still sell it in glass bottles. Not that it matter with Coke as it’s causing more deaths than anything…

The tricky thing is that not all chemicals can be tasted. You may filter water and find it tastes great but still has high contamination levels.

Hi Nick,

can imagine what you're talking about. Good point. Very good point!

I'll rethink some water storage tanks.

Thanks.
Good to know you're out there...

Cheers
Dirk

[Dirk01]

Originally Posted by peghall

Plastic water tanks must be cured differently from waste tanks...a good quality tank that's specified to be a water tank will not "seep out" anything.


--Peggie

Hi Peggie,

do you really believe in that? Or that anybody knows what he/she is doing or selling?

Peggie, I respect you more than you can imagine, bit I think in this case you're on the wrong road...

Cheers
Dirk

[Dirk01]

Originally Posted by s/v Jedi

The good quality water tanks, even though they don’t have food grade markings I think, still seep out chemicals. It is the amount and kind of chemicals that governments deem not dangerous to our health, but with the track record of having to come back from it over and over (we came from safely rated lead water pipes) you can bet any chemicals are bad.

Stainless steel is far superior. Even water from cement lined cisterns is better than from plastic imo..

Some searching online will show glass, ceramic and stainless steel being the inherently safe options.
Plastics that are rated safe, become unsafe after heating, damage like a scratch and calendar aging.

Hi Nick,

Unlikely you might be right
+ 1

Cheers
Dirk

[Icarus]

Originally Posted by s/v Jedi

I am afraid we live in a time where your health is not on the mind of those manufacturing and selling water tanks. You can not just “expect” you will be fine, you need to make sure. Like those “candle filters” so popular with offgrid living… there was no need for their independent test results… until someone paid to have it done and they failed big time.

Filters need official ratings and you must know what (incl. which chemicals) they are rated to block to levels safe for consumption. Many filters in use do not have those ratings.

I have done a lot of testing and the only time I can’t taste the chemicals coming from plastic is with a new polycarbonate bottle. When the bottle is a year old, I can taste it (and they have a due date printed on them).

My test is simple: take RO water, filter that through a NSF rated filter (like Seagull IV) then fill a stainless steel bottle, a glass bottle and the bottle (or tank) you test. Let it stand for 24 hours then do the taste test.

Most people can tell the difference between Coke from a plastic bottle or a glass bottle and this is why they still sell it in glass bottles. Not that it matter with Coke as it’s causing more deaths than anything…

The tricky thing is that not all chemicals can be tasted. You may filter water and find it tastes great but still has high contamination levels.

Coke is causing death?
Where did you get this data from?