With all due respect to @terry9 , I feel a larger volume tank, preferably squarish with filler is still the more effective method. I only mentioned the PVC tube as it seems to be used in ET arms. If the goal is to smooth out unregulated pulsating air flow, then some form of impedance and disruption will be required. A larger diameter tube is still directing air flow not disrupting it.
A squarish tank with inlet / outlet situated in a diagonal relationship and fillers in-between seems to offer the air path of most resistance. I liken the process to water filtration. You want the filtration tank to be large and the outlet to be small. Water flow then slows, with greater amount of sediment, and hence cleaner water out the other end. Anyway, that's my unscientific two cents worth :)
@spiritofmusic The Eheim seems to be the gold standard in the aquarium hobby. The Sera 275 that I am using has an output of min. 275 liter / hour. There are Eheim models with 200 l / h or 400 l / h. And it's the 'min.' in the Sera specs that is throwing me off. Are the Eheim specs min or max? I wondered if your client could shed some light?
A squarish tank with inlet / outlet situated in a diagonal relationship and fillers in-between seems to offer the air path of most resistance. I liken the process to water filtration. You want the filtration tank to be large and the outlet to be small. Water flow then slows, with greater amount of sediment, and hence cleaner water out the other end. Anyway, that's my unscientific two cents worth :)
@spiritofmusic The Eheim seems to be the gold standard in the aquarium hobby. The Sera 275 that I am using has an output of min. 275 liter / hour. There are Eheim models with 200 l / h or 400 l / h. And it's the 'min.' in the Sera specs that is throwing me off. Are the Eheim specs min or max? I wondered if your client could shed some light?