Roller Mat and Herbie overflow -- two questions...

[David3147]

1) Does a roller mat take the water as a full siphon (to keep the system silent) --maybe some one has a diagram of one?

2) side note, the tank I'm looking at has the main drain and emergency drain both the same diameter. If the first is on siphon, will the same sized emergency drain be sufficient? In the past, I recall the emergency drain is supposed to be larger.

many thanks!
-david

 

[vtecintegra]

Roller mat takes a full siphon.

My emergency is the same size as my two drain pipes.