gph

[fla pat]

I am looking to buy a new pump. The one I have now is rated at 465gph at 3 ft. The new pump I am looking at is rated at 500gph at 3 ft. how do you know what gph a take should be at?
I am replacing it because I do not know how old the pump is and understand that they need to be replaced. So how often sould you replace a pump. The pump I am looking has a three yaers warrinty, but I have seen you should replace every year or so.
The tanks is a 90 gal drilled with the overflow in the tank. The pump sets outside the sump. Is there a diffrence between a pump inside or out side the sump?
Thanks for the input.

 

[golfish]

I've never heard about replacing pumps when they get old. Now if its a RIO I would replace it with another brand.

 

[fla pat]

It is a little giant and I have no idea how old it is. It seems to run hot. And I am not a fan of oiling the pump. I am loking at mag drive pumps.

 

[squidd]

You have an external pump now,,,the Mag Drive would have to be run internal (wet) I've heard of them running externally, but there are heat, noise and leakage issues...
500 gph doesn't sound like alot(enough) for a 90 gal tank...do you have additional powerheads in the tank to increase circulation ?
How big (rating) is the overflow...built in or HOB...?
If your overflow will handle it I'd bump the pump up to 900 gph or so...even if that's the "rating" at 3 feet you'll probably see less than that in the tank depending on pipe size, elbows and outlets...

 

[fla pat]

thanks for the coments squidd. I talked to the LFS and he siad that it would be better to stay with the little giant. I do not have any other pumps at the time being. LFS sugestedI put in a corner pump to help with circulation.
The tank I have is made by all-glass pre-drilled. it has the rounded black plastic overflow in the corner. It has one return for the filtered water coming back into the tank. How do you know how much the overflow can handle? Is it not better to have more gph vs. just more circulation in the tank.
I also got a new maroon clown at the LFS and he seems to be doing great:happy:

 

[squidd]

Maroons are cool...I've got a 3 1/2" tuffy in my aggressive tank and he(she) don't take no Guff from nobody...including my 12" PV Lionfish...
AGA overflows are at a minimum 600 gph, so you could bump up your pump, when your ready to...
Gph, circulation and turn over are, and can be, used interchangeably...
The point is to get the water "moving" in the tank to keep oxygen levels up and "detritus" in suspension (to be picked up by filter)...
So whether it comes from overflow/sump/return or additional powerheads in the tank is not as important as getting the water moving at a good "flow rate"...10 X to 20 X tank volume in gph...or 900 to 1800 gph for your tank...
10 X is a "suggested" minimum, and 20 X is really not that much more...it's not like fish and corals are "blowing in the wind"...

 

[fla pat]

Thanks agian Sqidd. I have emailed all-glass too and they said that a 650gph at 3 ft. would be ok. So I think I will stick with the little giant pump but go up a size because what is in there now is a 465gph. I will have to change the pluming because the inlets are diffrent sizes.
Moroon seems to be doing well has not eaten yet but it has only been a day. :happy: