joe perry
08/16/2012, 12:55 AM
http://i1135.photobucket.com/albums/m624/joeperry5/2012-08-15_21-23-51_724.jpg
So this is the third impeller magnet i've had split on me in less than a couple of years. The other two were koralia magnets so I wasn't surprised. I am surprised that Tunze made the bearings and everything else bullet proof on my Tunze Silence pump but left that one weak link. A new pump, by the way, costs about $80 plus shipping and an impeller costs around $32 to my door. I guess they need to make money somehow but why not by making a product that is hands-down the best on the market? <end rant> So I noticed that the magnet rusts which causes the plastic covering to split. That tells me that either the magnet isn't completely sealed in from the get-go or the sealing fails after a while.
I googled "marine potting compound" because in the electronics field (in which I'm a novice) they do something called 'potting' electronic components or assemblies which encapsulates them. A good example of this is the processor on a throw-away calculator or a toy. My google search turned up a bajillion hits of course but right there at the top was a company that sells potting compounds for marine electronics. They had three materials to choose from. Epoxy, polyurethane, and silicone. I'm wonderin' if anybody out there knows, off hand, if any of these components are chemically inert in a marine aquarium. Although I know little about it, polyurethane would be my first choice just because I've witnessed a biofilm forming on (5 minute) epoxy and silicone just doesn't seem like a good fit for something that might get the occasional calcium-carbonate shard rubbed against it. Heck, even something like plasti dip might do the trick. Again though, I'm not nearly as familiar with reef-safe chemicals as some of you guys out there. Any thoughts?
So this is the third impeller magnet i've had split on me in less than a couple of years. The other two were koralia magnets so I wasn't surprised. I am surprised that Tunze made the bearings and everything else bullet proof on my Tunze Silence pump but left that one weak link. A new pump, by the way, costs about $80 plus shipping and an impeller costs around $32 to my door. I guess they need to make money somehow but why not by making a product that is hands-down the best on the market? <end rant> So I noticed that the magnet rusts which causes the plastic covering to split. That tells me that either the magnet isn't completely sealed in from the get-go or the sealing fails after a while.
I googled "marine potting compound" because in the electronics field (in which I'm a novice) they do something called 'potting' electronic components or assemblies which encapsulates them. A good example of this is the processor on a throw-away calculator or a toy. My google search turned up a bajillion hits of course but right there at the top was a company that sells potting compounds for marine electronics. They had three materials to choose from. Epoxy, polyurethane, and silicone. I'm wonderin' if anybody out there knows, off hand, if any of these components are chemically inert in a marine aquarium. Although I know little about it, polyurethane would be my first choice just because I've witnessed a biofilm forming on (5 minute) epoxy and silicone just doesn't seem like a good fit for something that might get the occasional calcium-carbonate shard rubbed against it. Heck, even something like plasti dip might do the trick. Again though, I'm not nearly as familiar with reef-safe chemicals as some of you guys out there. Any thoughts?