[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [APD] Re: Heating water for water changes


"Metals can build up in your water heater."

This is definitely true. If the metals build up in the water heater, is that
a bad thing for your fish? Let's examine the question.

First, where can the metals come from? Here are a few options.

1. The water itself.
	If this is the case, and they are building up in the water heater
(and staying there, I suppose) wouldn't the hot water coming out have fewer
"heavy metals" that the cold water going in?

2. Supply piping to your house.
	See #1 above

3. Anode in the water heater.
	Many people recommend adding zinc to your diet. There is more
magnesium (and calcium) in the tap water (in the form of hardness) at my
house that many of you would believe. The small amount that the anode would
add in a short time frame is probably undetectable, unless your water is
VERY soft. If you want to check it, measure the difference in hardness
between the hot and cold water.

4. Piping from the water heater to your hot water faucet.
	Doubtful if it is significantly different than that from the cold
water faucet. If it were, the hot water pipes wouldn't last very long.

One of the major causes of water heater failure is mineral buildup (scale)
in the bottom of the tank. This scale is cause by the tendency of some
minerals, mostly carbonates and sulfates, to precipitate at elevated
temperatures, generally above 120 deg. F. (I know that notion is
counter-intuitive to most people. Most of us think of hot water as holding
more of a substance than cold water, which generally is true, but not in all
cases.) This buildup causes hot spots on, and eventual failure of, the glass
lining, which then leads to increased corrosion and failure of the tank in
the form of leaks.

Even if your water heater were to remain unused for several days or weeks,
it is doubtful the deposits would dissolve back into the water. This type of
scale is very difficult to remove. Any place that uses water-cooled heat
exchangers can testify that they spend a lot of money to chemically treat
the cooling water to minimize scale formation, and more to physically remove
the scale that does form. Out here in west Texas (oil and gas country), many
exchangers of this type are taken out of service once a year for cleaning
and testing.

I won't ask for comments on this message, 'cause I know I'm gonna get 'em

Douglas Guynn 
        d.guynn at sbcglobal.net 

"The goal of Incrementalism is to present the depraved or offensive slowly,
progressively, and then more regularly over a period of time so it becomes
apparently normal." - Tammy Bruce
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com