Just wondering if anybody has used the inexpensive Koralia 'copies'? They are way cheaper than the genunine Koralias. I'm sure they won't last as long, but, whilst they are working, do they at least perform just as well in terms of the low pressure + high volume water movement that Tom recommends?
Ideally I would like to pulse the water movement, but it seems to cost a fortune for a controllable pump.
The Tunze Stream pumps also look good - is there a good cheap version of these?