Howdy,
Im still working out the appropriate Iwaki to use :oops: Essentially I need 850gph at the head of the sea-swirl (that’s its maximum rating) The head height is about 10 feet (a little over 3 metres)
The pump I currently have is an Iwaki MD-40RXT. According to the diagram in the PDF (http://www.marineandreef.com/shoppro/CA_Iwaki_Pump.html - it's the MD model, not WMD) the 40RX(T) flows at 840gph at 10 feet head which you would think is spot on – however this figure doesn’t account for pipe friction or bends etc.
The 55RT model flows at the same (if not less) at the same height. So, in theory I need to go to the 70RT. However, this (according to the diagram on the same site) does approximately 1,200gph (20gpm) which is 350gph more than the sea swirl can handle. The pipe going upstairs starts as flexible bilge piping (which I think may cause some problems being flexible loses flowrate) then through 2 x 45 degree bends (to get around a floor joist) then upstairs into 3 x 90 degree bends (1 x 90 degree heading horizontal across the top of the sea swirl, 1 x 90 degree bend down into the sea swirl then 1 x 90 degree bend out of the sea swirl into the tank. I dont know if the 850gph maximum rating is at entry of exit from seaswirl) The pipe is all 3/4†(20mm)
Question is, will the above friction and bends etc pull the flow rate back enough to the 850gph maximum rating? Personally I think 850gph is an approximate figure they give out and probably a conservative estimate so I would imagine it would really be capable of closer to 1,000gph.
Do you think the 70RX(T) is too much for this setup? If so, any alternatives?