sixxer,
I noticed you are going with concrete and thought this might be worth looking into. It is called Xypex -
www.xypex.com.
Background - I recently purchased a house and there was a slight leak in a basement wall. I had an environmental inspector guy come out to look at it and he recommended a product called Xypex. It can be installed on walls with
existing leaks. Their literature said it has been approved for use with potable water and foodstuffs. Part of the specs from their sebsite are below.
Bona fides for the envirnonmental guy - Second one I had out to the house. It had been shut in for a couple of years and there was some slight mold trouble that the realtor's inspector found and wanted a small fortune to fix. I called a friend of mine who is a commercial realtor. He put me in touch with a commercial inspector (does airports, hospitals, large buildings, etc.). This guy fixed the minor problems I had for just a few bucks in a couple of hours (about 5-10% of the other guy's bid and the other guy said he wasn't sure this would get it all) and told me about this Xypex stuff. He swears by it.
The only reservation I have is the part where it says it passes vapor. Allows the wall to breath without leaking. Not sure I understand this but it isn't the first time my understanding has been lacking.
I called the company to talk about a salt water application and mine. They referred me to a local rep I left a message with and will post with more info when I get it.
Hope this helps,
Charles
From the Xypex site:
Noticed the website was copyrighted and didn't want to do anything that might upset them or get RC in trouble so here is the link -
http://www.xypex.com/specs/spec-data.html. Notice that it is approved by EPA and Agriculture Canada for use with potable water and in contact with foodstuffs. Says it can be applied to interior ofr exterior walls and will work after the leak has already occured. Do not understand the part about letting the wall breath while still retaining water though nor how it would affect use on a concrete reef tank. They do show it used with swimming pools though.
Did a little more looking for the swimming pool apllications and found that it was used at the Shed Aquarium in Chicago -
http://www.xypex.com/projects/projects.php?mode=details&project=65. It says they did 120,000 ft2 in the 5 main exhibition tanks, including (if I read it correctly) a 2 million gallon tank housing their Beluga whales. Guess it will work with salt tanks.
Also check out