The way i understand it that Carbon tends to be more effective if the water is slowly flowing through it and if too much tumbling action can cause carbon to actually abrade itself into smaller pieces, meaning anything it absorbs can be released back into the tank.

Interesting. I have not heard this before. Maybe its good my carbon does not tumble then.

So I should have pellets in the first chamber full blast then slow it down with a valve to the second chamber with the carbon?

How is yours set up?

You might want to look at running two pumps...I tried to run pellets and carbon with a single MJ1200 and I wasn't happy. Now I run a MJ1200 on my pellet reactor, and a MJ600 on my carbon reactor and I'm happy. I've also noticed that if you're not careful, and push the rubber 90 elbows on the TLF reactors all the way down you end up cutting off more flow to the reactor, as the hose barb on the reactor almost butts up to the top of the elbow.

A half full TLF reactor with pellets BARELY tumbles correctly with a wide open MJ 1200. A 600 would work for a GAC only reactor.

If your return pump is large enough you should look at teeing off of it to run your reactors. I run a Vertex UF15 with bio-pellets, and a BRS reactor for carbon teed off the return line from the Barracuda. No more piddling around with MJ's clogging up etc.

I have one pump 1200 for each reactor because now i am using 2x Deltec FR-509 Fluidized Reactor, but i did have TLF 150 before and was also use 900 on carbon and 1200 on pellets (was just too small for size of my tank and leaking problem)

Also when i replace carbon or fill up pellets on each reactor, i want to able turn them off separately.

I am using a Maxi Jet MJ1800 on my TLF 150 and it works perfect. I had 2 -150s being ran by this pump without issues. Carbon should not tumble at all it defeats the purpose. I am switching to a NextReef MR1 and hope this pump will work as well as it does on the 150.

Thanks guys, a lot of good options and setups out there. Its going to take me some time to decide whats going to be best for my setup.

I was using a MJ1200, was working great, but wanted to cut down the number of pumps i had in the system, so I Tee'd off my return pump. My return is a dart gold, but i have low pressure since i'm dumping back to my sump for flow control. I had WAY more flow comming from my MJ1200. I don't think it's too little now, but more would be better, might go back.

As for people with issues of the tumbleing, make sure you get a mesh mod or sometihng for the reactor. the filter stuff that comes in there doesn't allow enough flow. With my MJ1200 i had too much flow and had to reduce it so the pellets would stop getting stuck in the top. You also need to clear out the stuck pellets every once in awhile, you should be getting LOTS of flow then.