I had one. It helped with algae somewhat running rowaphos in it but I didn't like the shoddy build of the unit. I guess that's what you get for $50. In about 3 months the 90 degree hose barbs hardened and came off on a regular basis. Just barely touching it would cause them to pop off and have water gushing out of the reactor.

It was noisy too leaning against the glass sump. The sump seemed to reverberate the noise from the reactor. There didn't appear to be a rubber seal on the screw on cap. It held with friction. Not a real issue with the lower water flow but in the long run I was nervous about the unit. I was worried about undertightening it and having a leak, or overtightening it and wearing out the seal.

It worked well though considering the price. I just wish that for the $50+20 paid for the reactor and a maxijet pump there was something all in one with a little more quality. There's not a whole lot out there at the same price range for competition so it's a good unit for the price.

[quote=fkshiu;282260]The reactor is simply a chamber to put media (whatever you want: carbon, GFO, etc) into. You then attach a small pump to the reactor which pushes water through. It's more effective than just a filter bag because water passes through and all around the media evenly.
QUOTE]

so the fuction is similar as fluval filter ?

I ordered some of these for the place I work at recently:

http://www.marinedepot.com/ps_ViewIt...ct~MN4111.html

I bought one and installed it Saturday, it does take up a fair chunk of space but I really like it and there is no chance it will leak.

[quote=Van-rookie;282303]Sorta, but the key difference is that the reactor operates at a much slower flow rate allowing the media to freely percolate which makes the media much more effective. In a canister filter like a fluval you have to use a media bag which results in a lot of bypass and the flow rate is also too high to optimize contact time.

i see.
would it be ok to take out carbon from the bag and put them directly on the compartment ?

Exactly.

Yes, you can, just make sure to keep the floss circle tops above and below your carbon.

I just asked this very same question in another thread I started a few days ago. I got one response saying they had done it. I'm doing maintenance to my reef tomorrow. Will then be running my Fluval 405 with 3 of the 4 baskets full of just carbon. No bags. At the top of the third basket I will use cut to size HBH carbon pads to prevent carbon bits reaching the impeller. The 4th (top) basket will be empty. This will probably allow me to increase my carbon use by 1.5x. I've been told you can't use too much carbon so I'm increasing the amount I use in an attempt to win some ongoing pest battles. But I digress and am getting off topic here.

Cheers,