Please don't be irritated with me, but I don't know what you mean by "29x25". (reef tank) The website only shows gph:
ModelFlow RateWattsDimensionsKoralia Nano240 gph3.52" x 3"Koralia 1400 gph3.52-1/4" x 5"Koralia 2600 gph92-7/8" x 5-7/8"Koralia 3850 gph102-7/8" x 5-7/8"Koralia 41,200 gph123-1/4" x 6-1/4"
so which one is right? thanks!!!