What do you need to know about them Stan? I'm sure someone here can help you out. I have two closed loops on my system, each powered by its own Sequence Dart. For my return, I have a much smaller pump, a Gen-X Mak 4. So far noise isn't too bad. The loudest pump is my Sedra 9000 on my skimmer, and that's mostly vibrational noise.
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32"x32"x20" Cube-ish tank
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