Neptune Cor-15 RPMs are always fluctuating...is this normal?

[Z Burn's Reefing]

Hey All,

I just upgraded to a Neptune Cor-15 as a return pump. I noticed the RPMs (running at 60%) are bouncing all over the place. I accepted small jumps here and there, but over the last 24 hours the RPM high has been 2210 and the low has been 2110...nearly a 100 rpm difference. Is this type of fluctuation normal? The pump is pretty darn clean, only a week old...do these pumps have greater stability if i turn it down some? Or perhaps turn it up? I was hoping for a return pump that was really tuneable and stable...kinda of disappointed...

Thanks for any thoughts and experiences for those who have run the Cor pumps.

 

[gbru316]

I find mine does this too. I occasionally have to retune my overflow because of it.

 

[Z Burn's Reefing]

I find mine does this too. I occasionally have to retune my overflow because of it.

Thanks! Yea....I am running a red sea tank and the constant adjusting of the down flow value (which controls water level in the overflow) is tiresome. I was seeing the water level dip a little in the overflow and so I adjusted the downflow value, but perhaps if I let it ride, the pump will increase RPMs again and balance itself out. Today I dialed the pump down to 40% to see if stability is a little better at lower gph.

 

[RoanokeReef]

Thanks! Yea....I am running a red sea tank and the constant adjusting of the down flow value (which controls water level in the overflow) is tiresome. I was seeing the water level dip a little in the overflow and so I adjusted the downflow value, but perhaps if I let it ride, the pump will increase RPMs again and balance itself out. Today I dialed the pump down to 40% to see if stability is a little better at lower gph.

Ever figure this out? Tired of changing it constantly.

 

[piranhaman00]

Switch to Jebao , problem solved

 

[Z Burn's Reefing]

Ever figure this out? Tired of changing it constantly.

To be honest, if the pump has been recently cleaned, things are relatively stable...but a couple months of use and just a little bit of build up...it starts fluctuating again. So at the moment I just have to run a lot of citric acid baths every 2-3 months...not ideal. I have noticed a little bit better stability of flow if I turn the pump up...I've been running it at 60%.

 

[RoanokeReef]

To be honest, if the pump has been recently cleaned, things are relatively stable...but a couple months of use and just a little bit of build up...it starts fluctuating again. So at the moment I just have to run a lot of citric acid baths every 2-3 months...not ideal. I have noticed a little bit better stability of flow if I turn the pump up...I've been running it at 60%.

I have to bump mine daily 2% to keep the speed up. What's strange is it's almost the exact same time each day ot slows down. I took it apart and it spotless. Working with Neptune so it will be interesting to see what they say. I love the extra features of the pump but it will soon be retired if they can't figure out what's going on.

 

[RoanokeReef]

Just wanted to update this, Neptune sent me a new driver and that sorted the issue out.

 

[gbru316]

In my case, I'm pretty sure it's due to 120vac amplitude instability. The rise and fall tracks pretty well with the EB832 voltage graph.

 

[Jalvarez12]

I have to bump mine daily 2% to keep the speed up. What's strange is it's almost the exact same time each day ot slows down. I took it apart and it spotless. Working with Neptune so it will be interesting to see what they say. I love the extra features of the pump but it will soon be retired if they can't figure out what's going on.

I’m going through this right now how do you get a new driver?

 

[RoanokeReef]

I’m going through this right now how do you get a new driver?

Neptune sent me one since I was still under warranty. However, it went back to fluctuating and what fixed it in the end was moving it to another Energy Bar.