Actually, it is 2250 gph -- sorry, typo on my part. Thanks, but I don't want to reduce it that much. For those who are curious, I am appending the thread from the Tunze forum on ReefCentral. One suggestion you'll see is to simply replace the prop with a 6060, caferacermike. However, the Tunze guy said: (1) you CAN safely partially block the intake of a Tunze Stream, (2) you can try up-angling (circa 10 degrees or so), (3) you can get a faux rock (or real one, Lonestar!), or (4) you can replace the prop with a 6060, thus making it have lower flow. I will try up-angling first, then the partial obstruction; then I'll see from there... ..Karl
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Tunze stream: reducing output?

Heya. I like sand in my tank. Sand is good; sand is wonderful; sand is all over my corals and LR. Ahhgh!

The 6080 is apparently just a bit too much flow. My tank is 60x18x21. I have the Stream positioned as high in the water column as possible, pointing it from the right-rear corner of the tank, towards the front-center pane.

Does anyone know how to knock off about 1/5th of the output? It is a 6080, so it's either On or Off. It puts out about 2250gph. Seems to me that if I restricted the intake screen, that that would reduce the outflow. But will that harm the pump?

TIA for any ideas/thoughts. ..Karl
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You can restrict the output but the other possibility is to angle it on a mag holder, slightly upwards or to use a Stream Rock which also angles it slightly upwards.

Roger Vitko
Tunze USA
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Thanks for your reply. So, if I understand correctly, if I block some of the intake slots on the cowling, it will not harm the pump. True? I can also try to angle it upwards: I'll lower the pump relative to the water column, then try some slight (10-15 degrees) angle.
Re: a "Stream Rock" -- I believe that that is a faux rock in which the Stream is mounted, yes? Thanks again for your insights! I really like the quiet operation of this pump, and am anxious to successfully use it. ..Karl
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Yes, you can safely partially obstruct the intake. The Stream rock is a ceramic rock that the Stream mounts in, it has about a 10 degree incline and from my experience you can use a much bigger pump with this slight incline, especially since the pump is usually near the bottom when mounted this way.

Worse case scenario, you can buy the blades of a 6060 and safely convert it to a 6060 though it will use a watt or two more due to the bigger coil, than a standard 6060.

Roger Vitko
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