hydor korilia powerheads

While I haven't had this problem myself, I've read that some others had this very problem with their brand new Koralias. Believe it or not, simply disassembling them and reassembling them was all it took to quiet them back down for those people. I don't know the exact reasoning behind this, but I would tend to think that it's just because the impellar or the bushing on the impellar shaft wasn't seated fully during the initial assembly. It's worth a try -- there's not much that comes apart on them, so you'll only have a few pieces to reassemble. Just keep an eye out for the thin bushing that's on the backside of the impellar magnet -- it's easy to lose.
 
Are there any tricks for better or more flow from the Korilia's? I just ordered 4 of them. I know the Maxi-Jets have an upgrade kit.
 
The difference is that with the maxi-jet upgrade, its changing the fundamental method on how the pump moves water, from a centrifugal-type pump to a propeller-type. Since the Koralia is already a propeller-style, you won't find an upgrade kit that will have the huge gains in flow like the maxi jet gets (on the order of 5x+ increase). You can get larger props for the Koralia though, I believe.
 
I thought I read somewhere, where you could do a prop change but can't find it now.
 
If u want higher flow get a koralia magnum I guess...
 
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