Right Size Pump?

DanSreef

Premium member
Hello everyone... I need some advice from everyone. I have a need to replace a Rio 2100 pump that I am using as a return pump on my 72 Gal Bow Front Mixed Reef Tank.

When I bought the tank off of CL a year and a half ago.... I did not even think of checking whether I have enough flow from my tank to sump and then back to the tank. I have heard in various places you should have 10-12x volume in gph circulation back and forth from tank to sump. When I look at the specs on the Rio 2100 it has 690 gph at 1 foot head height. At 6 ft it goes down to 200 GPH. Mine is around 4.5 feet high so I am guessing my flow rate is in the 300 or so GPH. At that rate I have no where near enough flow....at least that is what I figure at this point. Please tell me if my thinking is off! The tank is drilled with an overflow...that appears to be about a 1" - 1 1/14" diameter.

So, I am looking for a couple of things:
a) What flow rate should I shoot for
b) Any recomendations for in-sump return pumps

I am looking for muscle, quietness and durability.

One last question, I have been fighting a hair algae outbreak for some time. I run bio pellets... I am now running GFO... my tests show Nitrates and Phosphates at Zero... I use T-5 Lighting... 4 bulb 54watts each...and I replace them every 6 months.... and I just replaced them. I am keeping the algae from taking over....but I should be gaining ground at this point.... I wonder if the lack of flow from tank to the sump then back to tank could be a big contributor to my issues. I use 2 Koralias and 2 JBJ water movers to supplement water movement in-tank.

Thanks in advance for ideas, suggestions...

Dan
 
4 powerheads and a 2100 return pump sounds like adequate flow to me for that setup. Don't stress about overflow rate since you have all those powerheads contributing to your turnover rate in the display. Sorry I can't help with the hair algae problem thou.
 
Thanks Fishbeard! I know I have a lot of flow within the tank. Are you aware of any rule of thumb for turnover from tank to sump? Since all of the filtration is there... and I am running Pellets and GFO I would think there would be value to having more flow between the tank and sump.
 
Well I know my buddy has a 75 and hes running a quiet one 3000, also has several powerheads in his display and hes pulling plenty of skim in his sump/fuge. You dont want to have TOO much flow thru your sump or it decreases your skimmer efficiency. Just replace what you have with something comparable (rio 2100+ or 10HF, quiet one 2200 are the less expensive ones that get the job done)
 
more important than turnover rate, your return pump should match your overflow.
a 1" overflow is generally rated at 680 GPH.

imo id shoot for a 750-900 GPH pump. that way after head loss your pump will be around the same GPH as your overflow. this way your tank won't overflow and your sump won't go dry.
 
more important than turnover rate, your return pump should match your overflow.
a 1" overflow is generally rated at 680 GPH.

imo id shoot for a 750-900 GPH pump. that way after head loss your pump will be around the same GPH as your overflow. this way your tank won't overflow and your sump won't go dry.

I think you are WAY overrating, a 1" overflow line is "safely" capable of around 300-350 gph, a 1 1/2" overflow line is capable of the 700-900gph range.

You need to follow manufacturers headloss charts selecting a pump, not all pumps rated 700gph @ 1ft will produce the same gph rate @ 4ft , 5ft, 6ft, etc...
 
I think you are WAY overrating, a 1" overflow line is "safely" capable of around 300-350 gph, a 1 1/2" overflow line is capable of the 700-900gph range.

You need to follow manufacturers headloss charts selecting a pump, not all pumps rated 700gph @ 1ft will produce the same gph rate @ 4ft , 5ft, 6ft, etc...

im not over estimating anything. im simply relaying information i've seen on other sites, and in product descriptions.
 
Ok, I invite you to set up a drilled overflow, plumbed with all 1" piping, and pump water into your tank at 700-900 gph, then report back on the results. Not trying to be a (you choose the word) to you but I don't want someone else ending up with a wet floor from mis-information. Real world application and calculations on paper are totally different animals. Sure, math says a 1" pipe can handle maximum of so much flow, that I won't debate, I've seen all those same charts on a day to day basis at my job, what I disagree with is the use of those theoretical limits put to practical use.

For practical purposes on an aquarium, if you are aiming for the 600-700 gph range from your overflow, it would be wise to step up to 1 1/2" piping, the next most common size available. Or if design allows, a dual 1" overflow setup (which could still cause issues if one overflow clogs). Peace of mind outweighs pushing the limits of a mathematical calculation IMO.
 
Ok, I invite you to set up a drilled overflow, plumbed with all 1" piping, and pump water into your tank at 700-900 gph, then report back on the results. Not trying to be a (you choose the word) to you but I don't want someone else ending up with a wet floor from mis-information. Real world application and calculations on paper are totally different animals. Sure, math says a 1" pipe can handle maximum of so much flow, that I won't debate, I've seen all those same charts on a day to day basis at my job, what I disagree with is the use of those theoretical limits put to practical use.

For practical purposes on an aquarium, if you are aiming for the 600-700 gph range from your overflow, it would be wise to step up to 1 1/2" piping, the next most common size available. Or if design allows, a dual 1" overflow setup (which could still cause issues if one overflow clogs). Peace of mind outweighs pushing the limits of a mathematical calculation IMO.

heres my RSVP,
my tank has a single 1" overflow. 3/4" return.
my return pump is a mag 9.5 rated @ 950 GPH @ 0' head.
my head loss is approx 4'
my floor is dry.


i do find it funny that you won't go with calculated flow rates of overflows, but you do seem to go with the calculated flow rates of pumps.
 
A mag 9.5 is capable of 800 gph at 4 feet, using 1 1/2" ID piping or hose. This is directly from their own flow chart.

You get 43% of that flow from your 3/4" return line (physical limitation of flow). Assuming zero bends in your return line, that comes out to 347 gph. A safe assumption is for each 90 deg elbow you add a foot of head to your return line, and for every 45 deg elbow you figure about 8 inches of head.

Your system is flowing a heck of a lot less than you think, hence why your 1" overflow line is adequate.
 
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