Anyone using the Sine wave feature on return pumps?

[NickCage007]

So, with some of these new dc return pumps now having a sine wave feature, was just curious if anyone uses it. I run random flow return nozzles, and neros, so its not really needed, and i am also curious how the ato would have to be set, since it would most likely cause some variance in the return pump area of the sump, where my sensor, or someones elses float valve, ect, would be.
So, just curious, why theyd add the feature, it must be usable for some applications, somewhere..

Ive had this pump a year, and have never used the mode, but just curious, if anyone out there uses it, with an ato, and how you have it setup.

Happy reefing!

 

[Phil D.]

Sine wave is for a closed loop system, not as a return. Problem with sine wave when it's return pump is it would be raising and lowering the water level in the return chamber raising havoc with your ATO.

 

[User1]

Sine wave is for a closed loop system, not as a return. Problem with sine wave when it's return pump is it would be raising and lowering the water level in the return chamber raising havoc with your ATO.

This is true. It is also true with non Sine wave patterns as I experienced this with my Cor 15 and Cor 20 DC pumps. I have them mounted on opposite sides of the display. Random flow nozzles at the ends. Anyway I setup a virtual outlet in the Apex and tagged it Tide. Using the OSC function I had it flip every 6 hours on/off. Then set one pump to come ramp up to 80% and the other down to 20%. Next tide cycle they would switch giving me that left and right or incoming outgoing flow pattern.

The issue was the sump water level would vary as one of the pumps had longer plumbing so the water level would change. ATO would kick in. Anyway I also tried using the Cor's built in wizard to start one ramping up from 20% and the other ramping down. Similar issue while it worked great sump water level changed and ATO went nuts.

I think I can write some advanced code to produce an hour window or so that it doesn't change and let the ATO work during that window. Then off for the rest.

TL; DR - anyway fancy wave or alternating power for flow will mess with water level in sump which impacts ATO. At least in my case