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Q&A with Tom Neale

Fresh-Tasting fresh water

Fresh-Tasting fresh water

Q: What can you do about the water from your freshwater tank smelling and tasting bad?

A: I heard of a guy who tried to solve the problem with two bottles of high-octane vodka. He poured the first into the tank. He then tasted the water from the faucet in his galley and found that he hadn’t achieved the desired results. So he drank the second. He said the results were superb … for a while.

I’ve never tried that and can’t recommend it. Usually the best and simplest way to keep your potable water fresh is to keep the tank empty and dry when you aren’t using the boat. The dark, wet environment in a water tank is prime territory for the development and growth of all sorts of bacteria and other life that can cause odor. The problem grows worse with the heat of summer and surrounding warm water. If there is an inspection port, open it so that the tank can better air and dry out. A fan blowing into it would help. If you open your port, cover the hole with a hefty screen or other barrier in case you have a cat on board or, worse still, a rat or a lizard. Unfortunately, airing and drying out is seldom practical.

The next solution involves special additives made for this purpose. There are various treatments on the market that are advertised to “sweeten” tank water, and you’ll find them in most boating supply stores. Fortunately, people with RVs also experience this problem, and since they seem to outnumber us boaters — and since they don’t need products with “marine” on the label — you may find a much less expensive treatment in your local RV store.

Star brite markets an interesting product called “Water Conditioner” (No. 91504), which it says is designed to eliminate odors that emanate from the tank walls and piping. The product doesn’t purify water or prevent bacterial growth, according to Star brite, but works by applying a microscopic barrier coating on all hard surfaces, thereby preventing any odor-causing materials from going from those surfaces into the water.

Be sure to read and heed all directions and warnings on the packaging of any product you put on your tank. There’s seldom an issue of compatibility with treatment and tank material, but be sure to read the labels carefully in regard to that issue also. Obviously, you’ll want to make sure that the substance is approved for human consumption — a step that the guy with the vodka possibly overlooked. (I’m a bourbon man.)

We’ve also used baking soda, sprinkling several boxes into our 300-gallon fiberglass tank on our boat when it was new in 1979. The water tasted strongly from the new fiberglass tanks. We mixed it up as best we could by adding it with a strong flow into the tank from the dock hose. We then pumped out the soda water and found a marked improvement. We’ve used baking soda with other smells and tastes, and found it to be less effective.

In the old days in the Bahamas, when we were getting our fresh water by catching rain on the decks and from cisterns with lizards and frogs swimming around in them, we’d put a small amount of Clorox into the tank. This would help with smells, and I assume killed most germs. It often caused a dropout of particulates (I’m told it was little creatures that had been killed) that would make the water look cloudy and slightly brown, but this would clear up in a few days. I suppose it was because the dead particulates had settled to the bottom — not an overwhelmingly appealing solution. I do not recommend this. The substance as sold for laundry isn’t approved for human consumption, and overdoing it could cause disastrous health problems. I mention it because you often see it in the “how to be a tough cruiser” books. Use only products made and approved for the use.

The very best thing to do is always take on good water — if only we could. Water often has iron, sulfur or other “natural additives” that will cause odors, particularly when taken on in rural areas. If we have to fill up in an unfamiliar place, we give the water coming from the hose the sniff and taste test before putting it in the tank. If it doesn’t taste right, we run it first through a carbon filter element (preferably with a 5-micron rating) in a filter body that we keep aboard for that purpose. You can get these from The Home Depot or Lowe’s.

We also use drinking water filters at our galley sink. You can buy the add-on filter equipment from those same home-improvement stores. Most people with a moderate degree of handiness can install them. We then use GE FXULXC filter elements (high-quality filter elements also available from the same stores), which remove most odors and tastes and give us a great drink of water. The good drinking water is more than worth the cost. There is water filter equipment marketed especially for boats, but we’ve always found that the gear we can buy for home systems works well.

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