Reef Safe magnets?
 

I was thinking of using magnets for a few in-tank uses. Does anyone know if there are "reef safe" magnets to be had?

I think ceramic magnets may be the type I want, but I want some feedback and additional information on them.

I tend to agree with you, ceramic magnets would likely be the safest *if its the magnet type i am thinking of*, but if its that problematic take some paint or something and triple coat the magnet.

Check these out. Plastic coated, SHOULD be reef safe. You could always add a layer of epoxy to be sure. Or, cover any magnet in epoxy.
http://www.kjmagnetics.com/products.asp?cat=164

I was thinking that anything I got should be covered in epoxy as extra insurance.

Nice link! Thank you. I'm thinking that the one at the bottom of the page is the best size, but I worry about the rubber. Would I just cover over the rubber with epoxy, or remove it, then cover the magnet?

Kind of related, is the external magnet for a Koralia safe to put inside? I was thinking of mounting one low on my internal overflow - the magnetic disc would be in water inside the overflow

I would say yes, because its covered, but beyond that, I don't really know.

I would try to cover the rubber with a thin coat of epoxy. It might not stick to the rubber very well. They also sell uncoated magnets, which might be the way to go. You just need to be carefull not to drop or allow the non coated ones to smash together. Apperently they chip and break easily, thats why they rubber coat them.

I may go that route then. I want to make magnetic frag plugs for propagation purposes. I want to see how well they work.

Any recommendations on the type of epoxy? I would probably try something like SweetWater or another aquatic friendly brand.

Maybe this is a better choice (http://www.kjmagnetics.com/proddetail.asp?prod=RX054E) it says its epoxy coated and appropriate for seawater.

Now how do I go about figuring out what size/strength is appropriate for which glass thicknesses?

I don't really know for sure. I was thinking of doing the same thing as you, but havn't tried it yet. It might be really easy to cover it with a thin layer of putty-deltec or something similar.