Dual Water Tank connection

Discovery:
We have discovered that the two water tanks can be connected by turning the valve lever to 45 degrees (half way between Port & Starboard). Very convenient way to “balance the tanks”, or just to draw water from both at the same time.

Background:
Being in a marina more than usual here in NZ, with unlimited great shore water, we often get into situations that we run a tank dry, and/or the boat starts to lean because one tank is almost empty and the other one full. That made us think about changing to a different valve. Looking at the GROCO 1/2" 4-Way Tank Selector Kit (Four Positions - Tank-1 - Tank-2 - Tanks 1 and 2 – Off).

However, being cheap, and being in a place where getting the valve is difficult and expensive. We just tested to put the stock valve half way in-between Port and Starboard (see diagram to the right). It worked well. Water is now drawn from both tanks at the same time (without limiting the flow). If they are filled unevenly, they self-level through siphoning.  We love this "extra" functionality.

We will not use the “Dual Tank” position:

• Whilst sailing (avoiding filling water into, or over-filling the lee tank.

• When we truly want to know when we used half of our capacity.

Understandably, anyone that use one water tank as RO water only will not want to use this method.

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