Philip Lewis wrote:
Frederik writes:

To be precise: I'm not looking for bucket-type surge devices, but
internal, pump-driven wave creating devices.


I'm still not sure what you are meaning.
Are you looking for "tuned output of pumps" to create standing waves
or do you want a siphon surge.
Standing wave generation, really. I've found quite some info on the
siphon-based surge systems, but the standing waves seem to be relatively
unknown so far.

If I can find some cheap, tank safe, marine, water valve solenoids
I'd do this:

Plumb a trunk line the width of the tank with a solenoid controled
nozzel every few inches. one nozzel would be left unvalved as a
failsafe to releive pump pressure.

Each solenoid would then be switched on/off at random by a controling
circuit. Light timers could be used for a less random, but less
complicated control. (I'd consider using X10)
Thanks for the suggestion, but I'm kind of wondering if 'random' outputs
would not extinguish each other overall. Wouldn't a 'wave' require
orchestrated output of pumps to actually grow to some significant size?
I'm currently using 4 Tunze powerheads, with a controller to do the
timing and alternating between outputs. It works, but there are always
dead spots in the tank, no matter how the outputs are directed. I've
seen some impressive demos of the standing wave generators, so I thought
I'd give that type of system a go.

Frederik