Fluval flex how to reduce flow

Shove a sponge into the outlet if possible, or direct flow towards the closest tank wall. But usually a sponge block works.
 
If a 9 or 15....it has two nozzles...direct them towards surface and tank sides...
 
I used to buy stuff from a guy on etsy. He makes flex mods with a 3d printer. Lidpropzshop, nice slow flow spray bar.
 
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