Filter replacement - advice?


Plant Guru Team
Lifetime Member
Sep 23, 2007
South Florida
Hi Tom,

I would like your opinion on the following decision on whether/how to upgrade my filtration on my 180 reef ready with twin overflows.

I apologize in advance for the length of the post.

Current setup:

36X16X14(LxHxW) sump (about 20-30 gals?) with twin intake towers both filled with bio-balls. The water simply trickles over large filter pads, down through the balls, and into the sump.

Return is via a 1800 gph Mag Drive pump with a ball and check valve that splits in a T to the dual returns. Ball valve is wide open always.

I also have a 500 gph Mag Drive to power a Mazzei 584. The output of the Mazzei is stuck directly into the sponge of the 1800 sump pump. No ball valve on the Mazzei.

I also have a Magnum HOT 250 canister filter.

Proposed setup:

1. Smaller sump with only one tower. Main reason is to create space under the cabinet to get the rest of the new setup in there :)

I want to keep the sump as I like the skimming and no evaporation line.....

2. At least 1 OC or Nu-clear 25 micron canister or 2 in line if they fit under there. Too low to do the NC extension kit :(

At least one of the larger sizes, like the NC 533 or the OC 325.

3. A UV sterilizer, not sure what size, model, or wattage. Recommendations are welcome. I would like to plumb this in-line. However, if I get the OC, I can get the one with the built in UV....

4. I would also like to eliminate the 500 Mag drive and plumb the Mazzei in-line.

5. Iwaki MD40RLT or similar to drive # 2, 3, and 4.

The Mazzei, UV, and canisters would each have a check valve to control flow if necessary. These would then all be merged back into one line to be split back to the tank.

I was thinking of merging this one line of combined flow back with the output from the 1800 gph. The Mag would then act as a booster pump.

This flow would then go back to the dual returns.


1. Would this setup be better overall than what I have now?

I have nice clear water and no diseases, fish are healthy, and plants are doing well. My mech filtration would obviously be better with the canister, but is the UV any better than the nice biological filter I have now? Sump is very mature......

2. Is the MD40 big enough to power all of this? Or do I need bigger?

3. Should I just ditch the Mag 1800 and not try to fit it in?

4. I can keep the sump I have, but that only leaves room for 1 canister and to plumb the Mazzei, and no UV unless I really get creative with plumbing. I just measured and it doesn't look good under there..........However, to remove the sump is no easy task either. I had to remove one of the tank supports to get it in there.......

Would the canister and external pump be better than nothing? I feel so, but how much more do I really need?

Maybe a berlin style sump with sock setup?

Remember I need to get in there someday as well lol

Space is certainly an issue under there..........

Two additional questions re: your 180 Starfire that will help me:

1. Do you have all of your setup under the cabinet, or did you need to go outside or behind the cabinet a bit?

2. Can you please post a pic or two of the plumbing in situ?

I would love to see how it all fits with the sump, the OC, Mazzei, etc. I don't think I am the only one either........Jason can also finish off the PDF schematic........

Any other thoughts would be welcome.

I think this is my final upgrade for a while until I figure out how to move the MH fixture around the tank automatically :)

Thanks very much in advance.


Junior Poster
Sep 28, 2007

For the 180 that I'm going to buy hopefully sooner than later I've decided to do a Berlin style sump with a wet dry area that is completely sealed, essentially making a big ass canister filter with more bio capacity, more mechanical filtering capacity, and more chemical filtering capacity with the addition of easy cleaning. I'll be able to put my CO2 reactor(s) in it, my heaters, etc. The only thing inline I would have to plumb would be UV (maybe).

Just seems way better to me especially given the $$$ of the big canisters.


Plant Guru Team
Lifetime Member
Sep 23, 2007
South Florida
Thanks for the reply.

Had I actually PLANNED my 180 like yourself and Tom did, that is proably the way I would have gone........

Issue is that the tank has been a work in progress, as my knowledge and understanding increase (albeit slowly lol).

I am going to try the NC and a booster pump and different configs and see how that goes.

Experimentation, here I come.