"How about no scott" Depends on the wood and depends on the coins. Copper is not a good thing for the tank. Neither is tar which could be on the barrell if it is like other barrels I have seen.
If you want to do much mor work you can elimanate all the downsides. You can use metal lathe (home depot) cut and bend to shapes of wood. put a 2" coating of mortar on and make sure it is pushed into the lathe good. Use a tablespoon to trowl te surface smooth. Allow to start to set and then will it is still wet carve detail into each piece. Allow to set for 2 days and then paint with water bae exterior paint deluted 50% with water for the base color and striaght for detail. Allow to set for 2 weeks and seal everything. The sealers will not leach into the tank. I have worked in this media and it is possable to duplicate anything. I have a 135 gallon comet pound that I handcarved out of concrete with 5 waterfalls a congo vine and some very realistic leafs all carved concrete.
It may take some work but you have elimanated all your downsides.
wood is organic matter. In the warm water in your tank it will slowly rot. Some animals may bore into the wood. The rate of break down may be slow enough though to be managable. Give it a try and let everybody know. You may have the first ship wreck biotope here. could be very interesting. Look up what kind of animals would colinize a ship wreck like that and go with it.
Isn't wood made out of PHOSPHATE and NITRATE? Any wood that rots will contribute a massive amount of the nasty organics that you are trying to remove.
Why not make a fiberglass or plastic ship...
Metal will also decompose and pollute the tank.
The reason why shipwrecks in the ocean are ok is because the ocean is so vast that one ship won't make an impact, but in the closed, confined space of your tank it could be a disaster.
FWIW, I have had a large driftwood centerpiece in my FW CICHLID tank for more than 5 years. It was a commercially purchased piece on a slate base. The plecos eat the surface wood and some are said to need it. It has worked out well, but it does color the water over time. This has gotten less over the years, at first the water turned tan after only a couple of weeks. There would be different problems in SW, I suppose. Maybe you could culture shipworms.
Hey--wouldn't it be cool if you could hack off a hunk of some mangrove roots (and the attendant life) and set THAT up in a tank?
Why not add those little plastic divers?How about the bubbling treasure chest?No...no...I got it! One of those porcelain "No fishing" signs! Better yet...skip the reef and get some GOLDFISH!
Hey, popepain
The plastic Idea is the way to go. I have a peace of vacuum formed plastic that was made from a rock mold, so I bet you could make a wood mold and get a vaccuum forming company to turn the wood ship intoplastic for you.
The down side it might cost you. I wouldn't know though because I got mine for free hehehe.