Glued-In fuel tanks?
 

I have never had a problem with tanks mounted that way. I suppose that an inline filter would break up the foam [ if foaming should occur.]

The best way to avoid foaming is the reduction of vibration by carefulley balancing the prop and mounting the engine firmley to the air frame.

Hope this helps,

Roger

Glued-In fuel tanks?
 

The best foaming prevention is a ballanced prop....

I've hard mounted tanks often with no problems. I've also foamed them in place using expanding spray insulation (no vibration isolation to speak of from that stuff). As long as the prop's been ballanced.. no foaming.

What I don't lke about the 1 inch dia hole n the firewall and silicone glueing the tank in place: Its very likely to have fuel seepage past the silicone (ithe silicone ALWAYS releases from the epoxy coated firewall within a couple of dozen flights.) There's a glue called E6000 which does a better job.