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Canister filter and inline equipment--orientation question

5163 Views 8 Replies 7 Participants Last post by  willknowitall
Hi All.

I have a 30 Gallon Tank that is over three years old. I am in the process of adding live plants. Currently the tank is serviced by two filters: a Marineland HOB HOT filter and a Rena Filstar.

The inlet tube from the Rena currently have a Turbo Twist UV attached to it. I will be adding a CO2 system that will also be tied into the this inlet tube, as well as an inline heater. For a total of three pieces of equipment on the inlet tube.


1) is this even feasible?; 2) if so, what is the best orientation, CO2, then UV and then heater; 3) if this is not feasible, any ideas as to how I can keep everything inline without having to by another canister filter?


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i have a marineland canister going thru a up co2 diffuser and inline heater
my filter is over rated for my tank so i dont care if it slows flow down a bit
i also have a smaller canister filter running thru a up co2 diffuser and a uv sterilizer
the problem you may have is , if the canister filter has a high flow rate its not as advantageous to put a uv sterilizer on it , especially if you want to kill parasites
my uv is rated between 200 and 400 gph and my filter is probable putting out about 200 gph
at 3 to 400 gph it would probable be useless for parasites
the easiest things to kill are bacteria , then algae then parasites
and its dependent on flow rate and the power of the unit
i would also have the co2 first so it travals a longer distance before going into tank
You mentioned adding this equipment to the inlet tube.

The general wisdom is to attach inline objects to the outflow side of a canister filter rather than the inflow side.

First, this puts your equipment on the "clean" side, reducing the severity of equipment getting stopped up with muck and mire. Second, it is generally said that it is best to put flow restrictors on the outflow side of the canister filter pump. It is supposed to put less strain on the water pump.

What is the gph flow rating of your Filstar?
+1 external add ons are best on the discharge side of the canister.
Use your hot mag as the reactor, just run co2 directly at the input. I have seen a lot of people do it that way then put the uv and heater on the out of your other canister.
here's a follow-up question I wanted to throw in:

When you install an inline CO2 diffuser/reactor is it necessary to have the output totally submersed in the tank? I usually keep the output of my canister filter just barely beneath the surface, which causes lots and lots of surface agitation and even puts tiny bubbles circulating around the tank.

It seems like this might just be allowing much of the CO2 to escape into the air right there at the output. Should I aim my output down another inch to make sure that the CO2 stays in the water as much as possible??
My advice would be to adjust your outflow in whatever way you need to in order to achieve the direction of flow, force of flow, and surface agitation that you desire. Then, adjust your CO2 to compensate in order to achieve 30 ppm.

Yes, having the outflow totally submerged will increase the efficiency of your CO2 enrichment. Yes, less surface agitation equals better CO2 retention.

However, CO2 is affordable and the CO2 flow is easily adjustable, so I say manipulate your outflow to meet your circulation/agitation needs and then dial in the CO2 based on those conditions. Don't let the search for near perfect CO2 retention cause you to compromise on flow or surface movement if those things matter to you.

Don't go to the CO2. Let the CO2 come to you.

As far as using the Magnum HOT filter to diffuse CO2, that is what I am doing. I'd recommend using a glass diffuser underneath the inflow (to give off smaller bubbles which are less likely to cause problems inside a filter than large bubbles) and then angling the inflow just slightly shy of perfectly vertical. This way, the CO2 gets sucked into the side of the inflow rather than accumulating directly underneath, causing some larger bubbles to slide out and rise to the surface instead of getting pulled into the inflow.
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I'm no pro at this but here's what working for me. I have a 120g tall with pressurized CO2. Its being filter with 2 fluval 404's I one filter with the intake through a rena stealth heater and the exhaust is submerged about 2 inches below the surface. The other has the in take through a hagen surface skimmer, the skimmer gives me control over the amount of surface movement. The exhaust is through a home made reactor biult similar to the rex rig set up and then onto the tank through a rena stealth heater. I used the heater for the exhaust so that I'm forcing the CO2 into the bottom of the tank. Its been working for me for the last 5 to 6 months. Still on same 10lb tank of CO2 too.
i was i bit unsure of the original question too , about the inlet , outlet
but if you read carefully iannozzi says connectected to inlet from the canister
which is completely different from inlet to the canister
anyways you want the uv to be on the canister outflow so your not sterilizing the bacteria making its way in to the biofilter
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