priming a canister filter

[J-P]

Ok .. I really need help with this.

I have searched the net , and searched some more. Downloaded the PDF manual and am still having problems.

I did a water change in a tank that had an Eheim 2217 canister filter on it. The water level dropped and the canister stopped pumping. The water level never dropped below the intake valve.

I tried blowing IN the outlet hose to clear the air (go figure that blowing into an air line would clear it). Didn't work. I tried sucking on the outlet hose, didn't work. I tried turning the canister upside down, didn't work.

This thing is a serious PITA! Any way to EASILY prime it and get it running again?

[HGI]

I've never owned a Eheim, but I do have 2 canisters (fx5 and xp4) and if I were you I'd open it up, drain all the water out of it and start over from the start see if that gets it going.

[J-P]

the set up is:
Intake: From the tank to the canister.
Outlet: From the canister to a UV sterilizer, to the tank.

The UV sterilizer is just slightly above the level of the canister but the hoses are long. There seems to always be an air bubble suck (of various sizes) near the outlet in the hose.The hose actually does an "S" to the UV sterilizer. And it does it again from the UV to the tank. Now, I can't cut the hoses, and the owners said that it had been running over 1 year without a problem. In a power failure, it would "just start up again". We tried for 2 hours to get it going and nothing worked.

I know there are on off flow valves. All of these were "on" and the power to the unit was never shut off. Why all of a sudden with a drop in water level would the thing stop working?

When I tore it apart and cleaned it, it fired up again just fine. This time a simple water change cause it to shut down and we can't get it started again

[Pufferpunk]

Unplug filter. Turn all valves off. Take the canister offline. Take off the top. Fill to the rim with water. Open valve on lid. Replace top (water will squirt out of the top hose). Put back online. Turn all valves on. Plug in filter.

Always turn off all filters, when doing water changes.

[RTR]

I have dozens of Eheims and have for generations. There is unlikely to be any blockage that I have not suffered in some form.

First: Basic lay-out and engineering: Review all of the intact set-up. Any bubble which is regular must be eliminated - such as the one you describe with the in-line UV. Re-do the setup until a captured bubble is impossible. This is done by leveling or adding just the needed tilt/slope such that no capture or build-up is possible, or by shortening or lengthening flexible or rigid hoses. This is basic set-up and cannot be ignored. If there are places - such as over-the-side or back surface skimmers/overflows which are prone to flow-carried bubbles, add a recycling pump to 24/7 evacuate the chamber where the bubbles occur. I use the ones CPR offers with their overflows. They are also available under their own brand name. These are rarely needed (never for me) in canister connections, but if I needed such i would use it.rather than risk a blockage. I rarely piggy-back anything. If I need UV, it is shelved with its tubing and pump and is independently powered and operated. Flow rate is too critical to UV function to couple it with variable-flow equipment such a most filters incorporating any mechanical filtration. UV and such are always short-term need in my tanks, if at all, so are best alone for me.

Operational purges: Cheat. Have the tank full and canister intakes and return in position for operation. Canister power OFF. Close the return valves from the canister to the tank. Open the intake valves from the tank to the canister. I you have duplicates of the return valves, separate the existing valve pair. Connect a spare of the distal return to tank valve with that coupled to the Python hose. If you have no spare valve, unscrew the retainer ring and remove the return hose from the tank side - if this is not daylight at the tank surface, remove it from the tank before disconnecting the hose and capture the water contained in a bucket. Replace the distal canister-to-tank hose with the Python hose (adapters as required). Turn on the Python to suck water/air from the system, and open the canister return valve. Tilt/shake the canister gently to purge air/water to Python and waste. Invert canister to check for impeller chamber bubbles. Shut off Python and close canister in-line valves. remove whatever the Python connection involved and restore the normal canister return assembly. Top up tank as needed. Open canister in-line valves and power up the canister. It should flow normally.

I know that sounds complex, but trace it through mentally a time or two and you will see it basically simple. That is a variant of what I do to back-flush all my bio-canisters every month - it really is almost mindless after you have done it a few times.

HTH

[J-P]

I disconnected the UV sterilizer, and made sure all the plumbing was as straight as possible. I disco'd the quick release on the outlet side and let it drain into a bucket. Once it started flowing I turned off the valves reconnected it and fired it up. I then turned the valves open and lo-and-behold, it worked!!! A sigh of relief. I am still a little worried about the outlet patch because I had to move the clamp from one area to another so that it wouldn't leak It really should be double clamped. I'll get at that next time I am there if they haven't knocked the thing over.

[duke]

Hi , i'm running the same set up my self . 2080 ehiem 3 pro with the inline heater and UV sterilizer . i wish i could be able to post a pic of the set up but i cant . the solutuion to you'r problen is to minimise length and bends , the 's ' shape you discribed is your problem . buy right angle elbows insted . " when running your lines" ,importance in order is ......... length first ,.......... bends second.



hope this helps

[J-P]

actually that is that I did. I disconnected the UV sterilizer and ran the lines straight up.

[RTR]

90 degree turns are poor. A "sanitary bend' is far better, or two 45 degree corners in sequence together. The right angle destroys laminar flow.

[geronimo69]

90 degree turns are poor. A "sanitary bend' is far better, or two 45 degree corners in sequence together. The right angle destroys laminar flow.

Is this only for the bendible types of hoses on canisters? On my 150 gal, I run a quiet-1 6000 and the piping bends 90 degrees a total of 6 times. My flow is great... Does the fact that it's pv (or pvc, or whatever, the white pipe) have anything to do with it? I haven't heard this before. Thanks.

[RTR]

The ribbed flex tubing does help maintain laminar flow - but you always have a curved elbow with it, not a "real" 90-degree turn. The net function is a 90, but the flow is the equivalent of a sanitary bend. Maintaining smooth/laminar flow is key.

No pipe or tube is fully laminar - their is drag along the walls, but the core should be smooth flow. In hard plumbing, 90-degree elbow and Ts really hash up the flow. Loss of smooth flow is the equivalent of markedly increasing the length of the run due to friction and turbulence. The same function and losses occur with air ducts.