Blue/Green Water Color in Head???

[Paul Elliott]

I've got a salt water Groco K head (manual pump), and the residual water in the bowl turns blue after sitting for a couple of weeks. My boat has two heads, the same type, and the other one is trouble-free. This one hardly ever gets used, but when I inspect it after a few weeks I see this blue water, or evaporated blue-green residue in the bowl.

What's going on?

[Astrid]

algae perhaps, or maybe copper oxide?

[LakeSuperior]

You have metal in your plumbing and it is oxidizing??? (Just a quick thought)

[Paul Elliott]

Originally Posted by LakeSuperior

You have metal in your plumbing and it is oxidizing??? (Just a quick thought)

That's my guess too, but what metal? The head has been doing this for several years now, before and after a partial rebuild (flap valve, joker). I think it's time to remove the head completely and do the full rebuild -- perhaps I will find the copper penny someone dropped into the plumbing?

I've got bronze seacocks everywhere (with stainless ball valves), but the other head shows no strange color in the bowl water.

And no, it's not the vitamins I've been taking.

[Blue Stocking]

I have the short body Groco (EB, Ithink) and it does the same thing. I would guess its just the Copper precipitating onto the porcelain. On a strainer, e.g, it would show as the green patina. I strip mine every year, and there is no sign on any electrolytic action between the various metals.

[peghall]

I have a guess, but I need to know the answers to two questions first...

1. How old are your K and EB toilets?

2. Are you using any tank treatment that's blue or green?

[Paul Elliott]

Hi Peggie -- I was hoping you would stop by!

I have two identical Groco model K-H Hand-Operated toilets. They are probably circa 2001. I use no tank treatment at all. My boat spends most of her time in a slip, vacant. Once a year or so we go for a multi-week high seas passage -- that's the only time the head sees any real use.

The head with no problem gets used a couple times a month (pee only), and goes overboard through a Y-valve. The head with the blue/green stuff never gets used, but I occasionally pump salt water through it and overboard. I use that head area as a gear locker.

Now that you mention it, the head with the color problem may have some of that orange dye in the holding tank, from a marina visit many years ago. But the tank should be more or less empty. In any case, I should probably flush it out the next time I go offshore (or visit the pump-out station).