# Combining Canister Filter Outlets



## wedge22 (May 5, 2007)

Is it possible to take two canister filters, say 2 rena xp3's, and combine the outlet hoses into one? What I am thinking of is using a T connector to combine the 2 hoses in the back of the tank and then only having the one hose enter the tank. I'm thinking that the single entry hose would then need to be bigger to accommodate the extra water from the 2 filters.

___
.... |
.... |ZZZZZZZZZZZZZ 
___|

Something like this if this crude drawing makes any sense. Ignore the periods.


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## planenut007 (Mar 21, 2009)

I have 2 fx 5's running on 1 spray bar, no problems, but still using both outlet hoses, one on each end. Just make sure your spray bar is large enough to compensate for both filters without impeding flow.


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## wedge22 (May 5, 2007)

WEll that is kind of what I am asking I guess. How big should my outlet be with 2 tubes coming into it. 2x the size, 1.5 times the size?


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## RyanR (Apr 29, 2008)

Definitely doable... though I dunno how desirable it is. I'm a big fan of surface agitation.

The new hose should be twice the cross sectional area of the the current hoses (basically the inside diameter, divided by 2, squared, multiplied by 3.14).

Some quick math should come up with the answer... though I bet it's something a bit more than 1.5x

-Ryan


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## Stickzula (Sep 14, 2007)

What would be the purpose of doing this :-?

One ghetto way to size the outlet would be to fill a 1 gallon jug or a 5 gallon bucket and put the inlet hoses of the filters into the container so that they reach the bottom. Remove the media from the filter, turn on the unaltered filters, and time how long it takes to empty the container. Then build your spraybar or combined outlet or whatever you are planning to do and hook it up to the outlets, refill the container and time how long it takes to empty the container. If it takes the same time or less and you are happy with it you're done. If it is slower or the pressure is more than you wanted, enlarge the outlet and try again. Repeat as necessary until desired flow is achieved.


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## wedge22 (May 5, 2007)

Basically the reason for it is the Euro-top, or whatever it is called, on an acrylic tank makes it so you are limited on what you can do with inlet and outlet hoses. This makes it so surface agitation, looks, etc. are all thrown out the window. By combining the two outlet hoses into one I feel that you would be able to go with a more traditional setup. Such as a spray bar at one end shooting across the top for surface agitation.

The top I am referring to is in this post with a picture of one of the ends of the tank.

http://www.cichlid-forum.com/phpBB/view ... ight=hoses


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## RyanR (Apr 29, 2008)

OK. Just decided to tackle the math, and the ID of the new hose should be 1.41x that of the two input hoses. Mind you, it's been 15 years since I took geometry. :lol:

-Ryan


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## planenut007 (Mar 21, 2009)

I have the two fx 5's running into a 5 ft 1 1/4" bar with 1/4" holes every inch, flow meters read a constant 450 gph or so on each filter at about 30" head height. Mind you the fx 5's have a 1" outlet hose to start. I believe the rena has a 5/8" hose outlet, that being said, I would assume that a 1" bar would be fine, length depends on hole size in the spray bar.
I did the combo thing to clear **** from the tank, gives a much cleaner look and got surface movement all accross a 6 footer.
You will be pleased with the outcome.
Feed each end of the spray bar from each pump, and there you have it.


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## ancestral (Mar 10, 2009)

If both filters are the same kind and have the same output capacity, it can be done. And of course you need a Y-junction and hose wide enough to support doubled output. T-Junction will drop your output rate significantly since water coming from 2 outputs will "push" each other at the 90 degree turn. I'd recommend a Y-junction, with 5/8" or 4/8" entrances on 2 sides and 1" exit and hose on the third side.

If you use 2 different filters with significant output difference, the strong one may effect the weaker one negatively on the output.


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## BinaryWhisper (May 5, 2006)

I 2nd the Y junction. You do not want the flow from each meeting head on and fighting each other.


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## KaiserSousay (Nov 2, 2008)

opcorn: 
Well, did you do it yet :-? 
If so, how did it work for you :-?


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