Fresh water tank

[LUVYAPOP]

Was wondering if there is a certain type of purifier I should use in my fresh water tank? I have a 210 gallon tank, it wasn't use for a few years until I bought the boat. I cleaned out the slime and added some kind of purifier to the water as I filled the tank 3/4 of the way. I use the water every three weeks when I go out to clean the bottom of the boat, but maybe only 2 gallons at a time. Any recommendations for adding something that will allow the water to sit as long as I let it and not be stale?

 

[Comodave]

The best thing is to use the water. Do you have water readily available to the boat? If so just use more water and refill it more often.

 

[TripleGGG]

In RVs and now my boat I use a little bit of bleach. My boat holds 110 gallons of freshwater so I am using about 4 tsp if filling completely. Or about 1 tsp every 25 gallons. If there is something better or this is a waste of time I would be interested to know.

 

[Maerin]

Mr. G,

Your dosage is high. You probably have residual chlorine taste or odor unless you use a T&O (carbon) filter. Free chlorine has a taste threshold concentration of 0.6–1.0 mg/l. Chlorine at a 5.25% (household Clorox) concentration should be about 1.5 teaspoon (about 7.5 ml) to 100 gallons for a maintenance residual of somewhere around 1-2 ppm. Remember if you're doing dosage calculations for chlorine and you're using Clorox, you must include in your calculations that Clorox is not full strength, but 5.25%.
Despite claims of pathogens entering via the vent lines, deck fills, or the dry interior surfaces of the tanks, the water in your tanks should stay potable indefinitely. It seems that some folks are just squeamish about drinking the water from their tanks, and that's OK. In the 10 or 15 yrs. I've been participating in these forums/discussions, I can't recall one anecdotal experience where tank water was the source of illness or adverse consequence. We drink our tank water, have been for over 10 yrs full time aboard. We produce RO water when away from a dock source. I don't add Clorox, that's me. If adding a bit of Clorox is reassuring, go ahead and add it, but keep the dosage at a reasonable concentration.

 

[TripleGGG]

Mr. G,

Your dosage is high. You probably have residual chlorine taste or odor unless you use a T&O (carbon) filter. Free chlorine has a taste threshold concentration of 0.6–1.0 mg/l. Chlorine at a 5.25% (household Clorox) concentration should be about 1.5 teaspoon (about 7.5 ml) to 100 gallons for a maintenance residual of somewhere around 1-2 ppm. Remember if you're doing dosage calculations for chlorine and you're using Clorox, you must include in your calculations that Clorox is not full strength, but 5.25%.
Despite claims of pathogens entering via the vent lines, deck fills, or the dry interior surfaces of the tanks, the water in your tanks should stay potable indefinitely. It seems that some folks are just squeamish about drinking the water from their tanks, and that's OK. In the 10 or 15 yrs. I've been participating in these forums/discussions, I can't recall one anecdotal experience where tank water was the source of illness or adverse consequence. We drink our tank water, have been for over 10 yrs full time aboard. We produce RO water when away from a dock source. I don't add Clorox, that's me. If adding a bit of Clorox is reassuring, go ahead and add it, but keep the dosage at a reasonable concentration.

Thanks for the info. I just got boat to my marina which is on same water supply as my house. I'll dose it one time then forget about it.

 

[LUVYAPOP]

The best thing is to use the water. Do you have water readily available to the boat? If so just use more water and refill it more often.

Thanks for that. When in the slip I use the dock water. I'll start using my water tank. I'm curious as to how long it will take to drain it anyway. It actually won't drain completely since the spicket is 7" above the bottom of the tank. Don't think I'll use bleach, but will feel more at ease if something was in there. I do have an in line filter.