Water tank conundrum

evangeline44

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I'm replacing my 3 watertanks with plastimo type flexible bladders.
My query is probably basic physics but I just can't get my old head around the following quandry:-

Each of the tanks is fitted with one inlet and one outlet.
No breathers are provided.

When installed the Number 1 tank will be filled directly from the deck filler (this tank is higher up in the boat than the other 2).

Can I then pipe from its (the No.1 tank)outlet to the other pair of lower tanks (call them No.2 and No.3) Inlets via a Y connector?

I wish to draw water from one of these tanks outlets into the pumped system for the galley/heads and calorifier.

This leaves me with one unused outlet fitting on either tank 2or3 should this become a breather pipe or do I just blank it off?

Very confused:confused:
 
Personally I would pipe each outlet into a manifold leading to a suction strainer and the pump, with an isolating valve on each line. That way you can limit the effect of taking in contaminated water, or a leak on one tank etc. a bit more pipe, but pushpit plastic tube is not expensive.

Common the inlets in the same way.
 
If you rely on the outlet from tank 1 to fill the others, it'll take a very long time. You'd be better trying to run a large-diameter filler pipe to all 3 tanks. The outlets could be combined, with isolating valves as Grumpybear suggested.
 
I think to do what you want you need to join the outlets from tank 2 and 3 otherwise how will you ever get at the water in tank 3?
I also think pvb's point is quite important, the outlet pipes are a lot smaller than the inlet pipe. On a practical note you would need a hose diameter converter to join an outlet to an inlet.
 
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Until recently we had two bag tanks on Cecilia, one port, one starboard. Both were filled simultaneously via the 1.5 inch inlet hose and emptied simultaneously via their discharge hoses. Although simple, this was a pretty poor arrangement. Far better from a water management point of view to have had a diverter valve on the inlets and small taps on the outlets.
 
Thanks all for the responses,
Yes Tanks 2&3 will be linked via a manifold and all tanks will be fitted with outlet valves.
Impractical to link all tanks to fill simultaneously.

Still confused about the possible need for a breather or not at the end of the line in tanks 2,3 or both.
 
No, you won't need a breather in the system. Any air in the system would be forced out of the filler pipe during filling. Drawing water from the system merely compresses the bags and they do not need any air.
 
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