It doesn't get any easier since I have MJ 1200s with octura props lying around...
If you were to do it from scratch, it would require a MJ 1200 magnet, a piece of carbon fiber tube (or rigid airline tubing), and an octura 1440 (I bet a dumas 3004 would work too). If you have ever modded a maxi-jet before you could either use your existing MJ impeller or make a new one from these parts in your sleep. The one thing left is getting it to start the right direction every time. I imagine this would just require a stopper like everyone uses for maxi-jet mods.
I am not going to find out though because I have four of these in a 92 corner... I don't need or want a single pump to put out more than 1200 gph. If I did I am sure I would have a final version of this souped up koralia running in my tank in less than 30 minutes. I just messed with this one for fun. It has already been restored to stock and put back where it belongs in my tank
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