not exactly high flow for a block
 

Howdy all, this question is probably way more complicated than it probably sounds. anyway cathars design and several of the clones depend or maybe with the assistance of a very high flow pumps work well. what if your pump isn't exactly the highest flow. for example what about a 185gph or a 320 gph pump. I have a very limited space for what i'm going to try and a smaller pump would work much much better but i'm curious how the lower flow will affect performance. thanks.

The max head of the pump is going to matter a lot more than the max flowrate of the pump when you are using a restrictive block.

I saw absolutely no noticable performance difference between an Eheim 1048 (~160gph) and an Eheim 1250 (~320gph) for the White Water. I think there is a difference, in the order of 0.2C, after accounting for the extra pump heat that the 1250 dumps into the water, but 0.2C is something that's hard to pick up even with a CPU die sensor as it's quite within the realms of error.