Mp40s and foam covers

[Notsolostfish]

I just cleaned my mp40s for the first time the foam on my 150G. And my flow tripled. I had to turb them down 10% on both. To get my flow right again. Is the foam covers block that much flow?

 

[exnisstech]

I just cleaned my mp40s for the first time the foam on my 150G. And my flow tripled. I had to turb them down 10% on both. To get my flow right again. Is the foam covers block that much flow?

They do and they get plugged with crap pretty quickly. I tried them once but didn't keep them on long.