Using food colouring in water tank to confirm a leak

[TopherTO]

I suspect that my water tank">fresh water tank is leaking, but it's hard to know for sure as I can only see about 15% of the tank. I believe my only option is to add some food colouring to the water to confirm. Curious to hear from folks who have done this before. Are there any side effects I should be concerned about with this test?

This is my only fresh water tank and I'm worried that it may contaminate my water supply somehow. When I'm finished, I'll flush the coloured water out of the tank of course.

[peghall]

Anything that's safe to use in food is safe to use in your fresh water tank.


--Peggie

[George_SD]

I disagree that that's the only way.

You can fill it to a level that you can see/mark or to the vent loop exit (until it starts running out) and then leave it for a prolonged period of time without using water. Then check if the level dropped if you can see it, or by trying to top it off and see how much you need. It also may be better to just trace the water lines and verify it that way. Many people suspect water tank or connections, when in reality it's boat fittings, portlight seals and other sources of leaks that cause water ingress.

You will have to flush the tank multiple times to get rid of the color.

[Bowdrie]

Tank material?
Simple system, only a few fittings, or more complex?
Most leaks are from various fittings, or the pump itself.
I've used paper towels wrapped around fittings and come back the next day to see which one(s) were wet.