Are those EZ-Clone sprayers just standard irrigation sprayers? The ones I know can run from as little as 15 PSI, and each would put out 4 to 40 gallons per hour.
I guess 18 sprayers at 15 GPH each would add up to 270 GPH (4.5 gallons per minute).
Do you happen to know what pressure your pump runs at? Is the only flow through the nozzles, or does it circulate water in the bucket also? Your photo looks like a raging torrent or inverted showerhead!
The sprayers I'm used to from Antelco or DIG usually put out a 5-15 foot fine spray or "fingers" of fast droplets that seem like they would knock any rooting powder or gel right off the stems, and I would expect to be a little harsh on root hairs. The sprayers I have, at 20 PSI, can be used to blast caked soil off pots or tools.
The photo near the top of the thread seems to show large droplets being thrown high enough to bounce off the lid.
Is your cloner really that vigorous? I thought that a mist or the tiny droplets thrown up by vigorous bubbling were all that were needed for cloners.
(Disclaimer: I don't know and haven't tried myself. But I've often thought about ways to get a gentle mist or lots of bubbles from a small or intermittent pump.)