Advise on connecting canister inline

**iak** · 29th Jan 2014, 11:55

hi guy, i wanted to connect my two canister inline but i am unsure if i do so would it cause the rotor of the caninster to be damaged.
Can this be done ?
tank ==> Canister 1 flow rate 500L per hour ==> Canister 2 flow rate 750L per hour ==> chiller == > tank

**thebaldingaquarist** · 29th Jan 2014, 12:14

For this arrangement, you only switch on the filter with the higher flowrate.
For the other filter, take out the impeller and don't turn it on.

Side note, such arrangements often result in :
the total resulting flow rate is likely to be below 500L/hour. is it ok with you?
more hassles when maintaining the filters.

**iak** · 29th Jan 2014, 12:55

Thx you for you advise. Yes that ok with me. By the way,
If i turn on the 750L and the flow rate be down to 500L i understand as it due to the additional connections.
but what will happen if i turn on both of the canister ? will it cause any problem ? Just curious = x

**tetrakid** · 29th Jan 2014, 13:27

Originally Posted by iak

Thx you for you advise. Yes that ok with me. By the way,
If i turn on the 750L and the flow rate be down to 500L i understand as it due to the additional connections.
but what will happen if i turn on both of the canister ? will it cause any problem ? Just curious = x

I have not done this before but from what I can make out, if you connect two canister filters in series, you will have to consider :-

1)If only the 750L is turned on, the overall flow rate will not increase but decrease due to the added resistance caused by the media in the 500L. This may be the best solution if you intend to use the additional media of the other canister.

2)If both the 750 and 500L are turned on, the flow rate may increase slightly due to the assisted flow (reduced resistance) of the additional motor. The increase may be only very slight or none, so it is not efficient or worth it to waste power on the additional motor.

But if you operate both the canisters separately (with their inlet pipes fixed at the same spot), the effective flow rate will be the combined total of 700+500 L/hr. The increased flow rate may not translate into better bio-filtering.

**AQMS** · 29th Jan 2014, 16:20

Hi,im just curious,
What is your purpose to connect 2 filter in a series?
I have four connected to each other.

**iak** · 29th Jan 2014, 16:23

It was a spare canister so i thought of increasing more BB for my tank = ]
4 connect ? Wow. Does all have different flow rate ?

**Urban Aquaria** · 29th Jan 2014, 16:38

Since both filters have motors, i would recommend running both canister filters separately, that way you have more options to position the inflow and flows of each filter at strategic areas to cover dead spots and create better circulation in the tank.

In addition, with 2 separate filters working in a tank, you can have one still working while you take your time to clean the other, so there is less interruption in the filtration process when doing regular maintenance.

**iak** · 29th Jan 2014, 18:00

It's a good advice. Thank you all for all your valuable input.

**AQMS** · 29th Jan 2014, 22:20

Originally Posted by iak

It was a spare canister so i thought of increasing more BB for my tank = ]
4 connect ? Wow. Does all have different flow rate ?

If you want to increase more BB then it is best to run both filter separately,just like what UA explained.
Unless you want to have a prefilter, then it is wise to connect it together.
Mine have two different flowrate 500l/h and 350l/h.

**tetrakid** · 29th Jan 2014, 22:48

Originally Posted by zerofighterx101

If you want to increase more BB then it is best to run both filter separately,just like what UA explained.
Unless you want to have a prefilter, then it is wise to connect it together.
Mine have two different flowrate 500l/h and 350l/h.

Strictly speaking, when connecting two canisters in series, the addition of a pre-filter in the chain will only further restrict the throughput of the setup. However if the size of the tank and stock loading is not large, the throughput should be sufficient. A slower throughput may not be a bad thing, as it will allow more thorough bio-filtering of the water as it passes through the BB media. With this in mind, connecting the canisters in series may be a better solution, with or without a pre-filter sponge.

**Redember** · 29th Jan 2014, 23:36

i would prefer to have the 750lph canister up front pushing the water through the chiller and have the 500lph sucking from the chiller's output.

**iak** · 30th Jan 2014, 00:30

Both my canister have sponge and media. So somehow the 1st canister is unknowingly demoted to a prefilter.

I understand everyone have different placement for their canister, just hope everyone treat it as a food for thought.
I thought of powering both canister but i recall reading from a article that it will cause the rotor to be damage that why asking what's the theory behind it.
Meanwhile i have my set up with only one canister running 650L/h while the other canister rotor already taken out.

Never thought that canister placement can be like playing chess.

If you want to increase more BB then it is best to run both filter separately,just like what UA explained.
Unless you want to have a prefilter, then it is wise to connect it together.
Mine have two different flowrate 500l/h and 350l/h.

My main aim is to prevent dirt from clogging the chiller. Thus the idea of running the two canister in line.

i would prefer to have the 750lph canister up front pushing the water through the chiller and have the 500lph sucking from the chiller's output.

May i know what's the reason Redember ? Can share ?

How does this set up benefit you.

you can have one still working while you take your time to clean the other, so there is less interruption in the filtration process when doing regular maintenance.

This is a good idea. Although it's inline but both my canister have double tap so it maintenance shouldn't be that troublesome.

**AQMS** · 30th Jan 2014, 07:52

Originally Posted by iak

I thought of powering both canister but i recall reading from a article that it will cause the rotor to be damage that why asking what's the theory behind it.
Meanwhile i have my set up with only one canister running 650L/h while the other canister rotor already taken out.

I turn on all four filter motor and it has been running for 4years now. So far so good.

**tetrakid** · 30th Jan 2014, 08:55

If canister filters are operated individually and independently of each other, there's no limit to the number of filters one can use.

But connecting two or more canister filters in series is different. For one thing, if a preceding canister is much more powerful than the front canister, there can be some back pressure at the preceding filter, since water may not be able to be forced through the first canister effectively. Such back pressure of water may even cause damage to the motor of the more powerful filter. The problem should not arise if the motors of all the canisters connected in series do not vary much in power.

**pufferlover** · 2nd Feb 2014, 06:45

Run that 750 after that 500... switch only the 750 the difference between inline is to achieve better water for some whom use it as prefiltration or polishing while another way is to have the inlet pipe long inter connect both canister to achieve anaerobic activity for your tank... im running for a year 2 big canister with no issues water have always been good but ill say it this setup is solo... suggest you run both to boost up your filtration