Temperate Marine Aquarium

Ditto what Oriongirl said -- go with dry base rock.... you may want to 'seed' it with some of you local rock - especially if the local rock has some nice coraline algae like mine does...

Thats what I did for my temperate marine tank - a little local granite-based rock to introduce some temperate coraline, and lots of dry base rock -- plus a nice deep sand bed to keep worms and other 'critters' multiplying.

Also, add a good size skimmer if you can -- most protein skimmers will work exceptionally well in colder water (I get many more bubbles in my Berlin skimmer on my temp tank than my reef tank, using the same pump)...

I also try to collect from areas where there is a bit more seasonal temp variation -- usually coastal rather than deep waters, so the animals are more likely to handle temps in the 60's to low 70's...

I posted a small article on this here:
http://communitytank.aaquaria.com/articles/nativemarine.htm

Some of it won't apply to your setup - different fish - but the same basic concepts/techniques will work...

condensation can be a royal pain - some of the local public aquariums go for double-paned glass to fight it...

One trick if you are chilling the tank - you may be able to find cheap sheets of styrofoam insulation at a homeimprovement store or lumber yard - you can silicone it to the tank back and sides to help reduce temp change... also try to use pumps and lighting that won't add extra waste heat (ie external pumps rather than powerheads, lighting with vent fans...)

I put my native marine tank in the basement to help keep it cool and stable year round - at most it hits about 70 degrees...
 
As another said, get a refractometer. They're the best investment you could make. Don't waste your time always messing with conversions to figure out your salinity. Also, don't skimp on your chiller. Even an undersized model will still cost a lot, but will hardly do anything.
It's a good thing that keeping most temperate animals is easy, because there is almost no good, updated information about the subject out there. You might want to check out the article on temperate aquaria that's coming out in advanced aquarist.
http://www.advancedaquarist.com/2009/2/aaeditorial
 
if you're going to be stocking with fish that you catch when scuba diving you should also just find some rocks that you find while scuba diving, the life of them will be use to the cooler temperatures and it will save you a tone of money, same with the sand. LR is just rock thats taken from the ocean
 
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