Replacement water tank

[tonyiiiafl]

On my 390CPMY I have the 70 gallon potable water tank under the aft bed. It is sort square and approx 48” long. Appears to be more room for a larger tank. I saw the inside of the tank from the inspection plate and it looks like a science project. I use bleach each time I fill it, and use it for showers and washing dishes only when we are on the hook or a mooring. Has anyone replaced their tank with a poly one? If so, where did you get it. I would like to get a 100 gallon tank, same size but longer to fit in there. We have 2.5 days worth of water for myself and the bride, but wish to be able to stay 3 or 4 days. I just bought a water level gauge with a tank sending unit, so I will have a better idea of where I am at use wise. Any info will help, as I have the entire winter to order one and have it made. Thank you all again!

[g36]

Wow you use alot of water if using 70 gal in 2.5 days. we also have a 70 gal on my 405 under aft bed. Anyway heres the oem carver used. They have different sizes and will customize if you wanted. https://www.trioniccorp.com/marine-wate ... aste-tank/

[tonyiiiafl]

I finally got a float type gauge to install so we can better mon it or, actually we have no real way of knowing what we use. We have never run out, but the Admiral has that fear. Thanks, it is just what I was looking for.

[km1125]

If you're looking for some tank options, check out greatlakesskipper Dot com. They have "overruns" from manufactures and they ship quick and cheap. I just got two waste tanks to replace mine and it was HALF what I would have paid elsewhere.

My 3607 has 120 g of potable water and it takes us quite a bit of time to use. Mine are poly tanks. What is your tank made of? If it's any metal I'd avoid keeping chlorine in there. OK for shocking it in the spring, but it's corrosive to metal long term.

[tonyiiiafl]

Mine is aluminum. I have used a couple of tablespoons of bleach each fill up of after. I am going to check GLS.

[km1125]

I should add also.... if you're replacing the original tank, don't think you need to get one exactly the same. You could also go with two smaller tanks (that overall add up to larger than the original) if it makes it easier to fit into the space available.

My boat came stock with two tanks, but they are paralleled so they are essentially one tank. Each individual tank is 60gal. There is a simple "T" that's on the large 1.5" fill line that goes to both tanks. The "draw" line going to the pump just comes from one tank and the two tanks equalize level though the 1.5" fill connection. The vents are combined with a "T" fitting and run to one overboard vent.

[tonyiiiafl]

I have been thinking about the added 240 pounds the new tank would add to the stern. I have to look into the plumbing 2 tanks together thing. Thank you.

[bud37]

Source of the post I have been thinking about the added 240 pounds the new tank would add to the stern. I have to look into the plumbing 2 tanks together thing. Thank you.

Tony....is your current tank on the boat centreline now ?

[tonyiiiafl]

No, it is off center a couple of feet to port. It is under the aft cabin bed.

[bud37]

I guess what I am thinking is ,have you considered the balance of the boat if altering your water tank locations. Does your boat show a list to starboard when the current port side water tank is empty ? I know you have considered fore and aft.