Internal vs. External Pumps for 180 gallon reef

[SkyPapa]

...

What I'm calculating right now is the power draw for two Eheim 1262's will be roughly 80watts x 2 for a total of 160w.

A reeflo can match and beat the flow of two Eheims 1262's for roughly 105 watts at about the same cost of the equipment.

...

I would get the reeflo dart gold if your return can handle it or you want to valve it or run reactors and such.
I wanted to replace all mine with a dart gold when I set up the 180 but with the distances and heads of the tanks I run I would have needed the hammerhead pump, so I still have my assortment of pumps that all work and run externally.

 

[scolley]

I've got a Posideon, and while it is miraculously quiet, unlike most other external (non-submersable) pumps, it is a WICKED source of heat to my water. I've got redundent pumps, and in the summer with the metal halides on... I have to turn the Posideon off for 45 minutes out of every hour to keep from buiding up too much heat.

 

[fishdoc11]

I really don't think you could go wrong either way. My deciding factor would be if you have a fish room or seperate room to put a pump in I would go external because the external pumps (Iwaki, which is what I use, and Pan World are both good brands that will last years with little to no maintenance) last longer and transfer less heat as you have stated. If you are trying to fit everything under the stand I would personally go with the Eheims because of noise and space issues. Of course then your chiller is going to be comming on more often and making noise anyway.

Have you checked to see that your overflow can handle 1800 gallons? Most 1.5 " overflows, at least the megaflow one's that AGA etc...use only handle a little over 600 gph through 1. The restrictive part is the overflow itself in these instances though, not the 1.5" standpipe.

hth, Chris

 

[T Man]

efficiency versus distance

efficiency versus distance

On the Reeflo pumps, I notice that they have higher GPH compared to Panworld or other competitors with much lower power comsumption. Only drawback appears to be the max-head. Has this been issue at all for you?

The lower power consuming motors are commonly used in the immediate area (under or behind tank), whereas a pump in the 5K GPH/2-3amp range can be plumbed remotely upwards of 20+ feet away.

On the 210 gallon....The Dart/Snapper is just right for me @ six feet of HP on the closed loop - it's about as efficient as they come. The shorter the better on the Snapper for sure.

About my 125 gallon(with 1/4horse chiller)......I also have to agree with scolley in regard to the heat produced by the "can motor" of the Posideon, IMO the volute is too closely integrated.
But for lack of a better design, it's one of the most dependable pumps I've ever had the pleasure to own. Tinman

 

[oscar.millan]

I've got a Posideon, and while it is miraculously quiet, unlike most other external (non-submersable) pumps, it is a WICKED source of heat to my water. I've got redundent pumps, and in the summer with the metal halides on... I have to turn the Posideon off for 45 minutes out of every hour to keep from buiding up too much heat.

I considered Posideon until I started to find several people had the same issues of heat with these pumps. It's a shame, because most people agree that this is a quality pump.

I'm between Reeflo and Panworld pumps for now. Surprisingly, nobody has chimed in to support panworld pumps.

 

[oscar.millan]

I really don't think you could go wrong either way. My deciding factor would be if you have a fish room or seperate room to put a pump in I would go external because the external pumps (Iwaki, which is what I use, and Pan World are both good brands that will last years with little to no maintenance) last longer and transfer less heat as you have stated. If you are trying to fit everything under the stand I would personally go with the Eheims because of noise and space issues. Of course then your chiller is going to be comming on more often and making noise anyway.

Have you checked to see that your overflow can handle 1800 gallons? Most 1.5 " overflows, at least the megaflow one's that AGA etc...use only handle a little over 600 gph through 1. The restrictive part is the overflow itself in these instances though, not the 1.5" standpipe.

hth, Chris

Good points, I'm going to do everything undernearth my stand. I'm leaning towards external because of the increased flow and improve efficiency. I am working on a comparison chart that I will post tomorrow after I put everything on excel. Just to give you an idea:

With the Eheim pumps:
1262 x 2 pumps = 1800 GPH
80watts x 2 pumps = 160 watts
$169.99 x 2 pumps = $340

With reeflo dart:
3,600 GPH
155 Watts
$304

Double the flow, roughly same energy, cheaper (initial cost), and from the consensus less heat transfer to the water column.

Which leads me to my next item to research and report back on. How much flow can my overflown handle? Very good question, I will have to get back to you on this one. Reeflo Dart might be too much for my overflow to handle. I believe my overflow can take a 2" in PVC, again, let me check and get back to you.

Thanks for your input - you got me thinking.

 

[oscar.millan]

The lower power consuming motors are commonly used in the immediate area (under or behind tank), whereas a pump in the 5K GPH/2-3amp range can be plumbed remotely upwards of 20+ feet away.

On the 210 gallon....The Dart/Snapper is just right for me @ six feet of HP on the closed loop - it's about as efficient as they come. The shorter the better on the Snapper for sure.

About my 125 gallon(with 1/4horse chiller)......I also have to agree with scolley in regard to the heat produced by the "can motor" of the Posideon, IMO the volute is too closely integrated.
But for lack of a better design, it's one of the most dependable pumps I've ever had the pleasure to own. Tinman

Tinman,

Thanks for the info, I figured that with all the 90 degree turns in the plumbing, the higher max head would overcome some of the inherent flow restrictions, but it doesn't sound like this would be an issue.

Since I'm going to have the pump right underneath my tank, I'll likely be fine with the dart or snapper. Plus, I'm always trying to be as efficient as possible to save on energy costs, and the wattage doubles as soon as you get the higher max-head typically around 20' and higher.

Thanks everyone for your input, I will have the excel chart up tomorrow.

Good night for now. Please continue to leave your feedback and I will respond tomorrow.

 

[oscar.millan]

I have a chart for comparison between pumps. Does anybody have any experience posting a spreadsheet? I was thinking perhaps google docs might work, or I can simply do a print-screen and post as an image.

Either way, I'm sure others have wanted to do a side by side comparison. The chart has Pump model, Price, GPH, Watts, and Max head. It has really help in narrowing down my search and I want to share with the community.

Thanks!

 

[DolphinLVR]

I have a chart for comparison between pumps. Does anybody have any experience posting a spreadsheet? I was thinking perhaps google docs might work, or I can simply do a print-screen and post as an image.

Either way, I'm sure others have wanted to do a side by side comparison. The chart has Pump model, Price, GPH, Watts, and Max head. It has really help in narrowing down my search and I want to share with the community.

Thanks!

I would love to see this as I am planning my return pump or pumps for my 180 build that I will be doing.

 

[oscar.millan]

Hey guys, sorry about the delay. I got caught up replacing a pressure relief valve on my home water heater and I had to do my water changes.

I will post the chart tomorrow. Glad to hear there is some interest.

I've added two other fields that might be useful, cost per GPH, and wattage per GPH. I'll explain in more detail tomorrow and why that information would be useful.

Good night.

 

[Nova101]

If this was my decision I'd pick the dual internal pumps over the single external pump simply because the dual pumps back each other up. In addition, from a space saving perspective (I think you said everything under the stand) internal pumps allow a bigger sump. Heat would be dealt with, if needed, using a fan and additional topoff.

IMO the bigger the tank the more you need to plan for something going wrong. With dual pumps your tank would survive fine short term with one pump going down. With a single pump, even if you buy a second pump and have it ready to go in an emergency, what happens if the pump dies during a time when you are out of town? Will your tank watcher be able to swap in the new pump. And again, this assumes you buy 2 pumps so that this even an option.

 

[oscar.millan]

If this was my decision I'd pick the dual internal pumps over the single external pump simply because the dual pumps back each other up. In addition, from a space saving perspective (I think you said everything under the stand) internal pumps allow a bigger sump. Heat would be dealt with, if needed, using a fan and additional topoff.

IMO the bigger the tank the more you need to plan for something going wrong. With dual pumps your tank would survive fine short term with one pump going down. With a single pump, even if you buy a second pump and have it ready to go in an emergency, what happens if the pump dies during a time when you are out of town? Will your tank watcher be able to swap in the new pump. And again, this assumes you buy 2 pumps so that this even an option.

Nova,

Thanks for your reply. I actually had this idea in the back of my mind. I really like the concept of having two pumps that could back each other up. I'm always trying to remove single points of failure, which a double internal pump setup would accomplish. And when you add the space issue with externals, the argument isn't as clean cut as one might think.

The compromise comes in efficiencies of a single pump with increased flow, less heat in the water column, and reliability (although some might argue that internal pumps can be just as reliable as external pump).

The argument continues and in some ways thickens.

Elaborating on your points, I would argue that even a single internal pump (after one has failed) would be adequate for an extended period of time. Which would give you time to leisurely find a replacement. Let's say it failed on Xmas eve when all stores are closed for example.

But to counter this argument, wouldn't power-heads like a Vortech's or a Tunze's, etc, provide enough agitation to keep oxygen levels up? Although, probably not giving you as much time as a backup pump, it would buy some time until you find a replacement. Although not simple as if you had a second pump already running through your sump. No argument there.

Thanks again for your thoughts and comments.

 

[DolphinLVR]

I am going to be having my 180 built soon and I will be going with 2 drains (Center Overflow) and 1 return. I do plan on having a spare pump on hand in case of failure. The return pump will be located in sump.

 

[oscar.millan]

I am going to be having my 180 built soon and I will be going with 2 drains (Center Overflow) and 1 return. I do plan on having a spare pump on hand in case of failure. The return pump will be located in sump.

Dolphin,

What kind of pump will you use be using? I'm assuming internal.

 

[DolphinLVR]

Dolphin,

What kind of pump will you use be using? I'm assuming internal.

I am going to be using the Eheim 1262. For 1 return, I have been told that should do nicely.

 

[oscar.millan]

Here is a chart of the different pumps I'm considering:
<a href="http://s236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/?action=view&current=PumpChart.jpg" target="_blank"><img src="http://i236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/PumpChart.jpg" border="0" alt="Photobucket"></a>

If there are any that you think should be on the list, please let me know, it would be pretty easy to add them to the list and do the comparison. I will explain some of the values with their respective graphs in the next couple of posts.

 

[oscar.millan]

Here is a graph of the cost per gallon of flow.

For example: the flow for the snapper is 2,500 GPH @ a cost of $304.99. You divide 304.99/2,500 = $0.12. You are paying roughly .12 cents per gallon of flow per hour.

Notice how reeflo pumps are a much better value. The dart being the highest flow for the price @ .08 cents per gallon of flow per hour.

<a href="http://s236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/?action=view&current=Costpergallonofflow.jpg" target="_blank"><img src="http://i236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/Costpergallonofflow.jpg" border="0" alt="Photobucket"></a>

 

[oscar.millan]

On to energy consumption and efficiency.

Below is graph of the number of watts needed for every 100 GPH of flow.

Using the dart as an example, it uses 4.31 watts of energy for every 100 GPH of flow. Making the most efficient of all pumps in this evaluation.

<a href="http://s236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/?action=view&current=Wattsper100gallonsofflow.jpg" target="_blank"><img src="http://i236.photobucket.com/albums/ff11/oscarmillan/180%20Gallon/Wattsper100gallonsofflow.jpg" border="0" alt="Photobucket"></a>

 

[sarmo]

"If there are any that you think should be on the list, please let me know, it would be pretty easy to add them "
i would like to see bothe the Reeflo Hammerhead and the Dolphin 7500... if you could. i have both. the reeflo is my return and the Dolphin is on my closed loop.....

thanks

 

[oscar.millan]

"If there are any that you think should be on the list, please let me know, it would be pretty easy to add them "
i would like to see bothe the Reeflo Hammerhead and the Dolphin 7500... if you could. i have both. the reeflo is my return and the Dolphin is on my closed loop.....

thanks

Sarmo,

Thanks for your post, I guess I could have been more specific. Pumps that should be in the list for purposes of a 180 gallon tank, which is what this post is evaluating. Both the pumps you mentioned are likely for a much bigger tank.

Nevertheless I've crunched the numbers, which I hope helps you get an idea.

Dolphin 7500
Cost $396.95
GPH 7,500
Watts 410
Max head 22
Cost/GPH $0.05
Watts/100 GPH 5.47

Hammerhead
Cost $410.99
GPH 5,800
Watts 375
Max head23
Cost/GPH $0.07
Watts/100 GPH 6.47

I should note that the Dolphin brand only noted average and not max wattage. Whereas the Hammerhead number is "max wattage."

Interesting conclusion from the numbers, although you get more bang for your buck, i.e. more GPH per dollar. The large pumps appear to be less efficient than the smaller reeflo (dart and snapper) it will cost you more to get 100 GPH of flow.