Is it OK to hook up 2 reactors 'in series', run by one pump?

[20 20]

I would think so, but figured I'd ask. I've got two TLF reactors, one for Rowaphos and one for carbon. I could run each of them with their own pump, but would rather only use one pump. Pump would feed the first reactor (Rowaphos), the output from the Rowaphos reactor would feed the second reactor containing the carbon. Output from the carbon reactor would go back to the sump. One issue I'm not sure about with this is the flow rate through the carbon reactor. I know the flow is supposed to be farily slow through the Rowaphos, is that flow rate good for running through carbon in a reactor? Any opinions would be greatly appreciated!

[20 20]

Anyone ever done this?

[BLockamon]

The carbon won't fluidize, but that's not necessarily a bad thing. The bigest drawback I see is that the through-put of the carbon may not be high enough to keep the water clear.

[20 20]

That's what I was thinking. What should the flow through a carbon reactor be, as compared to a phosphate reactor?

[pjf]

Granular ferric oxide (GFO) requires a lower flow rate than granular activated carbon (GAC). Warner Marine’s PHOSaR (http://www.premiumaquatics.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=warner) may be an exception because it is in pellet form.

Is there any reason not to use a T-connector? You can place the GFO reactor on the branch of the T to slow the flow into it.

[20 20]

That's what I've got right now, but it's a bit clunky, and I could save a bit of space in the stand if I could 'redo' how I have them set up. But, it sounds like I should just leave it as I've got it. I'm still wondering what flow rate I should have through the carbon, I'm not sure the 'minijet' I'm using is pushing enough water through both it and the Rowaphos reactor. I've got valves on the inputs to both so I can regulate the flow to each so I limit the flow to the Rowaphos reactor to the appropriate rate. The flow through the carbon reactor is a bit higher, but I'm wondering if it's enough, could a higher flow rate through the carbon get better results? If so, what should that rate be?

[pjf]

Placing your reactors in series sounds like a good idea to simplify your setup. The GFO reactor should determine the flow rate because of the fragility of GFO media.

If you wish to increase the flow through both reactors, you can try to use the more durable PHOSaR pellets in your GFO reactor.

Another alternative that I will be trying later this month is to place both GAC and GFO in the same large reactor chamber. I'll separate them with a sponge pad and perhaps "sandwich" the GFO with GAC.

[ianward]

I have exactly your setup but I use the "T" connector with 2 TLF valve's to controll the flow through the individual reactrs.
Works like a charm.

[SDguy]

Aren't the reactors designed for virtually zero pressure? ie couldn't the slight back pressure caused by the second reactor make the first one leak? I know my phosban reactor's screw on top is pretty weak...not sure I would trust any sort of pressure there...

Anyway, not sure...just throwing out ideas.

[Toddrtrex]

I am running mine in series -- first one for carbon -- been set up for about 2 months now, no issues with leaking.

[gcarroll]

I have been running mine is series. PHOSaR in the first chamber. 1mm pellet carbon in the second chamber. Both fluidize well.

[20 20]

Seems like it's viable to run them in series, enough people are doing it and happy with it.

I still wonder what the optimal flow rate through a carbon reactor is, though. Slow like through a Rowaphos reactor? A bit faster? A lot faster?

[kau_cinta_ku]

i also run them in series. carbon in the 1st then phosban in second. i have fast flow in the carbon but using a ball valve have it slower through the phosban but i think it is still only going as fast as the phosban

[20 20]

If you have a valve in between the reactors, wouldn't the flow through both be exactly the same, no matter how open or closed that valve is?

[kau_cinta_ku]

yeah which is why i said "i think it is still only going as fast as the phosban" but either way each reactor will have the same flow when using 1 pump for both

[20 20]

Doh. Missed that part. :)

[pjf]

When placed in series, which reactor should be first, the GAC or the GFO?

[sjm817]

I used to run 2 in series. GAC, then GFO. You want the GAC 1st since it is less costly and will absorb DOCs before it hits the GFO.

[20 20]

Why don't you run them in series any more? Was there an issue with running them that way?

[sjm817]

I'm not using them any longer. Too small. I run carbon in a canister filter.