How is a simplicity 1000 pump outdoing a cor15?

[Hincapiej4]

I gotta be doing this wrong.

Somehow my simplicity 1000 pump is pushing more water than my cor15.

I gotta be plumbing this incorrectly.

I talked to brs they told me to get a 3/4 in. CPVC-CTS Slip x FIPT Adapter Fitting and a 3/4 thread to 5/8 barb. I got a 3/4 thread to 3/4 barb, and the rpms went lower but I don't think it is pushing more water.

I got it and got the cor started. It's nowhere near the same gph as my previous pump.

Far as I can tell, the pump itself is a 1" outlet and I put a 3/4 flat seat barb and screwed it in.

Should I just look for anyway to convert it to 1" to 3/4 in the least amount of hardware possible?

I don't know jack about plumbing and I've exhausted any searches I could think of

 

[lapin]

Age old question that is pretty common
https://www.irrigationtutorials.com/outlet-pipe-size-for-pump-is-a-bigger-pipe-better/

 

[Girlsfish2]

Honestly, maybe take that the Simplicity 1000 is outperforming your Cor15 as a sign of build quality. Paying for an expensive pump does not mean it is a better pump.
My Simplicity skimmer outperformed my Reef Octopus skimmer and I take that as a sign that maybe people overpay because of brand name but the quality of some of the more affordable versions are as good if not better.

 

[Hincapiej4]

Possibly. I'm thinking I'm just a dumb a haha