# Eheim 2217 - length of tubing?



## Swamplander

I've looked all over the Eheim manufacturer website, downloaded manuals and checked retailers but can't find out long the tubing is that it ships with or what the max distance is for the tubing.

My new tank is going in an area that's under consturction. I'd like to put the canisters in a cabinet, but that's through a wall (requires cutting) a short distance (total tubing would be ~15' for each input/output).

While the area is still under consturction, I'd like to have my contractor do the cutting and finishing of the holes if the distance will work (specifically because it invoves cutting into a cabinet that he has better tools for. I saw where on one site it said it was 458 (input) 5/8" and 459 (output) 1/2"... wasn't sure if that was the modele number of the piping, or if it is 458". If the latter it's plenty.

Anyone care to share how long the tubing is that ships with the canister?


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## newforestrob

if I got this right ,you want 15 feet for input and output(total 30 feet of hose),well I can tell you it doesnt come with that much,I think around 10 ft,as for the hose diameter its 16/22mm ,meaning the inside diameter is 16mm and the otside diameter is 22mm
or 5/8" inside diameter,what you could do is buy some clear tubing at a hardware or plumbing supply store it would be alot cheaper than eheims tubing


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## AeonzMike

I bought 2 eheim 2217 recently, got the second one last friday in fact. The 2217 comes with 2 different tubing size: 
Intake tube is 16mm/22mm (inside/outside diameter) and 4 feet long.
Output tube is 12mm/16mm and also 4 feet long.

You will also get 2 valves that will add a couple of inches to that.

In the manual it states that the max distance between the surface of the water and the canister should not exceed 180cm (about 70 inches).

Mike


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## newforestrob

thats interesting that the 2217 comes with two different size hose,my pro 3 is just one size(16/22)


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## AeonzMike

newforestrob said:


> thats interesting that the 2217 comes with two different size hose,my pro 3 is just one size(16/22)


I was pretty surprised at first but then it kinda made sense.. you get more pressure by having a narrower tube on the return. I have no idea if they were always made like that or only the new models.. also on the box they call it eheim classic 600 in some places and 2217 in other places.


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## 702Cichlid

Just as a caveat, be prepared for it to move a lot less water having to push 15', it will probably still function but it won't be as effective; as a pipe length increases, the restriction due to friction and pressure also increases. I would definitely shoot an email to eheim and ask them if the motor can even handle an output line of that length before i added any customizations to my house.


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## Swamplander

Darn... I don't want to decrease the throughput of the canisters. I can figure out another mounting option... :/

Thanks for the insight on the tubing.


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## dotbomb

Pressure loss in a horizontal straight run of pipe/tube is pretty minor. Just don't clutter it with fittings and you should be fine. If you are pumping vertically 15' I'd say there might be a problem.

Assuming this is a horizontal run of tube I say buy the stuff you need from a store with a great return policy and see if it works. My bet is it works just fine.


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## dotbomb

You can also increase the diameter of the tube to reduce pressure loss (lower velocity = less pressure drop).

Experiment before punching holes in your house though.


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## 702Cichlid

Absolutely don't take my word as gospel. I would check with eheim customer service as they're usually pretty god about helping with questions. Even if there is little drop off for an extra 9 feet of hose on the output side there could be issues on the input side having something that is normally siphon fed over four feet doing so over 15. I'm not a hydraulic engineer I am simply theorizing that that impeller motor is designed to push a certain volume of water against gravity (if a 6 foot hose that's roughly 378 ml which has a mass of 305 grams and now asking it with the same power to push 900 grams of water up the same distance if you have a 15 foot hose). I would think, even with my basic physics background, that even assuming no loss of efficiency for pressure or friction you're still asking the same pump with the same power to do more than twice the work. I would think there would have be some loss of system efficiency without even factoring in that more work will need to be done to pull the extra 9-10 feet of siphon.

For example, my xp3s recommend no more than 10 feet of hose be used combined between input and output connections in total for optimal efficiency. And that same filter has a higher power motor and moves more gph than the eheim.

Honestly, it's all conjecture and honestly I think it would work, I just don't think you'd get your factory spec gph doing it. If it's something you'd like to do you could pick up a filter and experiment or shoot eheim customer support a line.

*edited for bad math*


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## dotbomb

Pumps are designed to specs that include fluid density at the inlet, inlet pressure (inlet head), and deltaP (pressure change between inlet and outlet). This deltaP must overcome "head" (or gravity in your post above) as well as all frictional losses on the outlet side.

As long as you are not significantly decreasing the inlet pressure you will avoid cavitation and the pump will pump fluid. IF it is cavitating then you need to increase the inlet pressure. There are 2 ways to do this. One is to stick the inlet tube down further in the tank. The other is to lower your canister even lower beneath the tank.

If you hear a grinding noise it means the inlet is causing cavitation.

If the pump has to work harder because of losses on the outlet side you will notice this in terms of decreased flow.

You can call eheim but you can also just run an experiment in your home. Again, my bet is it works just fine assuming your tubing is horizontal for the additional 15'. The real work is in pumping up elevations and pumping through fittings (elbows Ts, reducers, etc) and frictional losses in smooth tubing on horizontal runs is minimal. The exception to this is if your velocity in your tube/pipe is really high then you end up with large frictional losses in the tube which means you need a larger pipe/tube.


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## 702Cichlid

@ Dotbomb - that makes sense, like i said i'm not a hydraulic engineer and my physics is limited to classic/mechanical physics, so already it seems like you have more depth in the field than i do. I guess increased mass and inertia don't apply as much as i think they would in a hydraulic setting like this, and i had that drilled into for a few too many semesters for me to ignore. My brain simply wants to stick those Newtonian physics rules that work is tantamount to energy, and work is defined as an applied force over distance, therefore increasing the distance is increasing the work and energy required and since the pump has a finite amount of energy to put into the system, using a classical model it would have to be less efficient.

However, where i'm probably losing touch with reality is how much energy is required to move that amount of water horizontally? Out of pure curiosity's sake, at what point would a horizontal length of a smooth-vinyl tubing finally give enough pressure/friction to restrict the flow?

@Swamplander - Dot seems to have a much firmer grasps of actual physics of the situation, you may want to lend more credence to his advice than mine.


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## dotbomb

I can't tell you for certain but it depends on the velocity in the tube.

I would assume the flow rates produce laminar flow and the velocity is relatively low in their tubes so that's my basis for saying that horizontal runs aren't going to produce much of a pressure drop in a smooth tube.

But yes, the work required is increased by distance but in the case of a fluid traveling in a smooth tube the frictional losses are minimal. You get such a larger magnitude of pressure loss in fittings and in elevation changes that the straight length of tube is negligible compared to the overall system's pressure loss (that is assuming the velocity in the tube is within reason).

edit: Designing pump circuits used to be the tedious part of my previous job.


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## Swamplander

My horizontal drop off is about 4', but I think that what I'll do is wait to get the canisters and do a little test between two buckets of water. The tubing is so cheap at my local hardware store ($0.33/ft) that it's worth the test. I'll see how it does with a 6' vertical change & 15' of tubing on both sides and see how fast it empties one bucket & fills the other up.

I was hoping to get my contractor to be the one who would cut the holes int he wall, but it's not the end of the world if I have to do it as it isn't hard.


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## dotbomb

I just looked at the pump specs for this canister. The delivery head is 7' 6". Your 6' elevation change might be a problem if the pump can't work against that head height on the outlet. Best way to know for sure is to experiment.


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## Swamplander

Have to say I'm surprised after my experiment... got two 16' tubes from my local hardware store. I first hooked up the canister a drain & fill a bucket; the canister was on the ground and the bucket was on the highest shelf I could put it on with the length of tubing provided.

I then hooked up the two 16' tubes I got today to the canister and moved it clear across the garage, still on the ground, and moved the bucket up another shelf to where the top of the water line was maybe 6.5'-7' high.

My only test was with touching the outflow to judge the pressure and I can't tell if I lost any pressure. The canister was able to empty the bucket with the OOTB tubing just a tad bit faster than with the 16' tubes.

Now, only trick is to find a different tube that has a thicker outer diameter. The outtake tube is fine but the intake tube's ourter diameter wasn't thick enough to provide a secure connection with the screw-back clamp on the canister. Back to the hardware store... but now I can take the double-tap to ensure I get one that's just right (all the options at my hardware store are in inches and not in milimeters... and the conversions don't give me an exact number).

Thanks for all the responses!!!!


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## dotbomb

Glad it worked! :thumb:


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