How can I adjust the water flow on my Magnum 350 canister filter?

Should I use the on/off switch (moving it to the left) or adjust the white valve on the output hose? I don't want to damage the filter, but sometimes the flow is a bit much, especially at feeding time. I've been just turning it off for feeding. Thanks.How can I adjust the water flow on my Magnum 350 canister filter?I have that type of filter, and to be honest I don't think you can control the flow.

live.com

cemetery plot