Water treatment with hydrogen peroxide

Howdy folks,

Now that our boat is spending more time in the marina we'd like to prevent our water tank from getting funky. Does anyone have a good resource for how to calculate exactly how much peroxide we should be adding on a per gallon basis?

We have the higher 27.5% peroxide on board but want to be sure we use the right amount.

Thanks,
Erin

Thanks Hayden,

As other folks mentioned on the thread you linked to, unfortunately we're not on the boat regularly at the moment (couple weekends a month). The previous owner did do us the favor of plumbing the system so it's fairly easy to sterilize the lines with bleach water, a bit of a pain but not bad.

I believe the problem is that we're not pushing enough water through the system to keep it fresh. It's currently not bad, but I'm concerned about keeping it from growing anything nasty. I had heard it was possible to do this with peroxide and the previous owner left us a half bottle of the concentrated stuff but am not sure on the amounts.

Also in the thread you linked to, it mentioned a recommendation for a filter to remove chlorine from the water when filling the tank. We've been using a filter every time we fill but I'm not positive it removes chlorine, is there a specific type you recommend for this?

Thanks again,
Erin

We use the same concentration that you have on board, acquired from a pool supply store. One ounce for each 20 gallons has worked for us. Read the label if it still has one (or google the MSDS) and use proper precautions. Re chlorine: the charcoal in the filter is doing the work. I have measured the free chlorine in the water on both sides of our filter, and it helps, but does not remove all of the chlorine. Hope this helps.

I have owned my IP-35 for 21 years. For most of that time I have filtered the water going in with a charcoal filter to remove the chlorine in an effort to abate the calcium formation inside the tank. I treat the tank with ordinary grocery store hydrogen peroxide, using about 16 ounces to a tankful. I have never treated the lines with chlorine (though I have replaced them once), but will start doing that as well. If my boat sits for a couple of months in the Florida sun, I do have to run the facets to get the foul smelling water out of the lines. After a few minutes the water smells and tastes fine, which supports Hayden's theory that it is the lines that are the problem.

Does anyone know if the peroxide is harmful to t\he membranes in Spectra Watermakers?