Eheim 1260 meshwheel maxed out at 15LPM?

[shelburn61]

I got my DIY eheim 1260 meshwheel up and running today. My skimmer is 5 feet tall so I am force feeding force feeding the Eheim with a linear air pump. I expected to be able to feed 30+ LPM of air through the pump, but I'm getting burping of large bubbles and increased bubble size when I increase air flow beyond 15LPM. What's the problem?

The air intake in housed within the base box with the airline running down the outlet pipe. This is a mockup of the pump intake inside the base box: Airline taps into 1" PVC tee. The horizontal tee outlet connects to an open end 1" pipe to pull raw water entering from the from the other side of the box. The bottom outlet of the tee is fitted with 1" -1/2" reducer.

3 layers of mesh. I bored out the volute cover as much as possible to be more like the 1262. The pump runs very quietly and starts up on its own without any air flow so I'm pretty sure there is no problem with the impeller being imbalanced or rubbing within the chamber.

 

[shelburn61]

no one? Is the 90 elbow on the output too restrictive?

 

[mgranato]

That's the first thing that pops out to me. One 90 is restrictive, but two may be too. It's a good starting point.

 

[shelburn61]

<a href=showthread.php?s=&postid=13938245#post13938245 target=_blank>Originally posted</a> by mgranato
That's the first thing that pops out to me. One 90 is restrictive, but two may be too. It's a good starting point.

Yeah, but removing that 90 requires entirely reworking the the pump mounting so I'm hoping to rule out other possibilities first

What would cause the pump to burp large bubbles? Is the air inlet too far from the volute?

 

[dew2loud1]

The air intake is quite a ways from the volute, the air is most likely joining into a large bubble before the volute and causing the burps in the skimmer. The two elbows on the outlet are also limiting the pump a lot.

It seems to me it would be pretty easy to tap a hole right in the union to introduce air right by the volute. I would leave the bottom air input as well. You might be able to get slightly more by splitting the air input into both places. I think moving the air intake closer to the volute and removing or at least upsizing the elbows larger will help significantly

 

[shelburn61]

There is only one 90 elbow on the output. The fitting within the reaction chamber is a Tee not an elbow so it shouldn't be very restrictive...

 

[chadfarmer]

5 foot tall

 

[shelburn61]

<a href=showthread.php?s=&postid=13944922#post13944922 target=_blank>Originally posted</a> by chadfarmer
5 foot tall

It's force fed by an air pump. Why would head pressure make any difference?

 

[Racing1]

<a href=showthread.php?s=&postid=13943147#post13943147 target=_blank>Originally posted</a> by shelburn61
There is only one 90 elbow on the output. The fitting within the reaction chamber is a Tee not an elbow so it shouldn't be very restrictive...

That 90 elbow is killing it. Need to get rid of it and move intake line closer to the volute.

 

[shelburn61]

OK. tapped the union for the airline right below to the volute cover. Little to no improvement - still getting large bubbles burping from the pump output @ >16-17LPM.

Now I'm wondering if lack of restriction before the air input is allowing the pump to pull too much water. I didn't think a "venturi" would be necessary with the air pump, but maybe I need to restrict the water intake so the pump can handle the volume of air being forced in?

 

[mavgi]

<a href=showthread.php?s=&postid=13949508#post13949508 target=_blank>Originally posted</a> by shelburn61
OK. tapped the union for the airline right below to the volute cover. Little to no improvement - still getting large bubbles burping from the pump output @ >16-17LPM.

Now I'm wondering if lack of restriction before the air input is allowing the pump to pull too much water. I didn't think a "venturi" would be necessary with the air pump, but maybe I need to restrict the water intake so the pump can handle the volume of air being forced in?

I replay to your message .

 

[BeanAnimal]

Mavgi... could you post the reply in public so others working with the eheim can benefit?

Force feeding meshwheel and needlewheel pumps on taller skimmers is a seldom discussed subject. My OR3500 starts to choke at anything over about 20 SCFH on a 6' tall skimmer.

 

[mavgi]

<a href=showthread.php?s=&postid=13952430#post13952430 target=_blank>Originally posted</a> by BeanAnimal
Mavgi... could you post the reply in public so others working with the eheim can benefit?

Force feeding meshwheel and needlewheel pumps on taller skimmers is a seldom discussed subject. My OR3500 starts to choke at anything over about 20 SCFH on a 6' tall skimmer.

IMo the eheim not so good on tall skimmer unless the mount high on the body (like the H&S style) i did test the 1260 & 1262 on 30 " high and i was not happy this pump can pull max 15-16 LPM when it's Ricric style if it's mount down to the body the pump hardly do something .

I told you in the past i want to send you pump to test

give me few weeks i need to finish few project and i will send you 2 different pump to your tall skimmer and like that we can see if it's good or not , i want you to try them direct without Force Feeding i am not sure but maybe it can work . hope you got 1" hole for the outlet this is improtant .

 

[shelburn61]

Mavgi,

<a href=showthread.php?s=&postid=13952559#post13952559 target=_blank>Originally posted</a> by mavgi
IMo the eheim not so good on tall skimmer unless the mount high on the body (like the H&S style) i did test the 1260 & 1262 on 30 " high and i was not happy this pump can pull max 15-16 LPM when it's Ricric style if it's mount down to the body the pump hardly do something .

This is only applies with a standard air intake right? Head height should be irrelevant with a force feed correct?

Bubble size in the neck is great until I adjust air input @ >15LPM. At this point, the pump starts spitting out large bubbles that disrupt the foam head. Hopefully these pics will help:

The neck is 4.5" OD x 12" tall. Reaction chamber is 36" x 8" OD
Bad pic, but you can see where I tapped the 1" union right below the volute. No improvement. Results were the same with the air input lower down on the TEE fitting. There is no "venturi" on the pump input so without the air pump turned on the pump pulls nothing. I wonder if I need to add a basic venturi to force the pump to pull air rather than water?

 

[shelburn61]

Bean,
Do you have mesh on the OR 3500? I think your "choking" issues are mostly a result of the relatively shallow volute on the OR.

The deeper volute on the Eheims, Sicces, etc. allows them to handle more air. Hahn, claims to have gotten 30LPM out of the Eheim, although he never produced the pics
http://www.reefcentral.com/forums/s...&perpage=25&highlight=eheim mesh&pagenumber=1

 

[Pbrown3701]

you are running salt water for your testing right?

 

[mavgi]

<a href=showthread.php?s=&postid=13954151#post13954151 target=_blank>Originally posted</a> by shelburn61
Bean,
. Hahn, claims to have gotten 30LPM out of the Eheim, although he never produced the pics
http://www.reefcentral.com/forums/s...&perpage=25&highlight=eheim mesh&pagenumber=1

I never believe Eheim can pull 30 LPM with mesh mod or the normal volute.

as far as the skimnmer , 4.5" neck can handle max 20LPM with good buble size more then that the bubble will be big .

the problem also is that even if you put venturi on the pump it will not work so well since the pump will chock . for this mod the pump was need to be high on the skimmer body. the only pump that i think will may handle it is the laguna 1500 .

you can see 42" skimmer 8" diameter 4.5" neck feed only with laguna 1500 6 foot pipe length and the original volute no air pump .

 

[shelburn61]

Right, with the 4.5" neck 20LPM is all that I am after. If 20 LPM is possible with the Eheim at no head, I don't understand why the force feed wouldn't allow me to get that with the pump mounted low on the body?

 

[BeanAnimal]

<a href=showthread.php?s=&postid=13952559#post13952559 target=_blank>Originally posted</a> by mavgi
IMo the eheim not so good on tall skimmer unless the mount high on the body (like the H&S style) i did test the 1260 & 1262 on 30 " high and i was not happy this pump can pull max 15-16 LPM when it's Ricric style if it's mount down to the body the pump hardly do something .

I told you in the past i want to send you pump to test

give me few weeks i need to finish few project and i will send you 2 different pump to your tall skimmer and like that we can see if it's good or not , i want you to try them direct without Force Feeding i am not sure but maybe it can work . hope you got 1" hole for the outlet this is improtant .

I would be glad to test a few pumps out for you Mavgi. I can try them without force feeding, but fear that the skimmer height will be prohibitive. The outlet is current 1" adapted to 3/4" unisial, but I can certainly change that easily.

 

[mavgi]

<a href=showthread.php?s=&postid=14008009#post14008009 target=_blank>Originally posted</a> by BeanAnimal
I would be glad to test a few pumps out for you Mavgi. I can try them without force feeding, but fear that the skimmer height will be prohibitive. The outlet is current 1" adapted to 3/4" unisial, but I can certainly change that easily.

today i will do some test on the 1500 and will send you some info & if this one will not be good enough , i got the 2400 & the 4200.... if you can send me PM with your email i will send you some photo and test. i saw your skimmer and i think that the laguna can handle it without force feeding but real test will show if it's good or not.