Pump Suggestion for overflow return

[MikeP]

I have a 90 gal (single overflow)which I will be setting up I am going to have a 30 gal refugium.
The overflow is 1" line into the refugium and a 3/4" line back into the tank. I figure it will be around 3.5 ft lift to the tank looking for suggestion for the size of a return pump.

Thanks

[galleon]

Iwaki 40 RLT

[Nubytuesday]

I definiely know nothing but I have the exact same aet uo and went with the 30rlxt because it still should push more water than the overflow will allow and is made for less resistance like a sump return with less use of electricity

[Nubytuesday]

30rlxt- 960 gph at 4ft 115 watts
40 750 gph 219watts
40 rlxt 1200 gph 219 watts

I do not believe the overflow will handle more flow
without modification you didnt say what brand if it is an all glass with overflow kit the manufacturer says 600 gph is it Im hoping for 800 the lfs says 700 will be it

[Nubytuesday]

the 40 rlt puts out less gph with more electrical drain & you can always cut back the preassure
please correct me if you feel differently

[asmith]

I would plan on around 700 GPH for that size overflow. I won't recommend a pump for you since that is not my specialty. However, I would rather buy a pump that is too large and throttle it back instead of buying one that can't keep up with the overflow.

Andrew

[Doug1]

Actually its OK to go a little less than max flow, it will be quieter I prefer slower flows thru the sump for several reasons, noise, bubbles, and salt creep all over the place , among them. If you do macro refuge, slow I believe is good, dwell time allows the macro to do its thing

[Nubytuesday]

I thought 10times circulation through the sump circulation was best so in a 90 gallon tank you need 900gph for reef
at less than manufacturer recomendatioins you would be less than 6 imes
So do I have this all messed up & only need the 10 times in the tank itself

[Doug1]

10x + circ is good, but not nesseccarily does it all have to go thru the sump. thats one of the reasons closed loops are popular, cheap, quiet high flow rates

[1BadHawk]

Ive found its easier to pick a pump based on the the size of the drain. Reason being, you dont want a pump that will out pump the draining capacity of your overflow.

Find out what your overflow capacity is and then pick a pump that meets that capacity or slightly less at includeing the head pressure.

Good luck

[Nubytuesday]

Thats easy if you know how to calculate for the bends you might have.

[David Grigor]

I used to have a 2700gph return pump on a 190g. When designing my 320g I went with a smaller return pump Mak4 and like Doug mentions handled the rest in the tank.

If your planning to have other circulation than just from a return IMO, the minimum flow should be slightly higher than the output of a skimmer ( if you even choose to have one ).

For a 90g something 500+ would suffice and really a personal prefference on exactly how much flow you think you need through the sump.

I have 2 30rlxt pumps and certainly can't say anything bad about them but $200 pump may not be in the budget, also output of the pump is 1" if you locked into the 3/4" you'll loose flow with that pump......

On a budget Mag7 or 9 is pretty decent pumps.

The sen pumps haven't heard very good track records on the impellers and wouldn't use for a return.

Mak4 is also a decent pump with 3/4" output that would be a good substitute and comparable to the 30lrxt for about $75 less.