Sump - a Nitrate Factory

Edwin Ho

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I was considering a canister filter for my marine aquarium instead of building a sump. But I was advised by my regular aquarium outlet that a canister filter is like a "nitrate factory". Despite that I explained that I planned to keep only two clownfish and later one sea anemone, I was advised that I will be better off to have sump.

Do you agree with the statemement that a canister filter is a "nitrate factory"? My tank is a 125 liters Juwel Rio 125.
 

Fish Fan

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Load your canister filter with mostly rock rubble, little to no mechanical media, and you'll be fine. It's the mechanical media specifically that causes a "nitrate factory". Many use a canister filter for their reef tank, wouldn't be my first choice (I personally hate canister filters), but it's possible. @FUNGI runs canister filters successfully.

Good luck!
 

VintageReefer

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Load your canister filter with mostly rock rubble, little to no mechanical media, and you'll be fine. It's the mechanical media specifically that causes a "nitrate factory". Many use a canister filter for their reef tank, wouldn't be my first choice (I personally hate canister filters), but it's possible. @FUNGI runs canister filters successfully.

Good luck!
Completely agree. Use it as a contained sump and fill with liverock rubble. You’ll be surprised what you see growing on that rock in a few months. It will become a cryptic / dark filtration zone with sponge and pods and filter feeders
 

vlangel

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A sump is good if you want extra equipment like skimmer, roller mat, reactors of any sort so they are out of sight.

However if you want to run a simpler system, a canister filter with rubble rock can be an easy solution to a very clean looking display. The Oase canister even has the heater built in so the only equipment in the display is a powerhead or wave maker.
 
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Uncle99

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I was considering a canister filter for my marine aquarium instead of building a sump. But I was advised by my regular aquarium outlet that a canister filter is like a "nitrate factory". Despite that I explained that I planned to keep only two clownfish and later one sea anemone, I was advised that I will be better off to have sump.

Do you agree with the statemement that a canister filter is a "nitrate factory"? My tank is a 125 liters Juwel Rio 125.
Disagree.
You just got to keep the canister clean.

This tank has no sump but has mechanical filter and skimmer only.
IMG_0032.jpeg
 

twentyleagues

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I have run saltwater tanks on hob filters, hob fuges, canister filters, and sumps. Sump is my favorite for many reasons but all of them worked. Canisters if set up correctly work fine. I hate doing maintenance on them though so I just left it with only live rock rubble and pulled the mechanical sponges out. A long time ago I stopped using mechanical filtration on reef tanks. I might use some floss every once in a while, or a sock but mostly I just dont. If you set up the canister like people are saying above it wont become a nitrate factory. The same goes for a sump or an hob filter if you use mechanical filter like floss to catch debris and you dont remove that and replace it regularly like every few days what it catches will indeed rot and become the nitrate factory you dont want. This is one reason people say this about canister filters. If you set up the can like @VintageReefer says the stuff that does get caught on the rubble will be eaten by pods or worms and if the can doesnt have mechanical filtration to get blocked up by debris it will continue to cycle the debris throughout the tank allowing things to use it. Same idea I use on my sumps keep stuff suspended and either used by stuff in the fuge section or recycled into the tank for corals and other inverts to use. I also like skimmers and yes a skimmer is a form of mechanical filtration. But it does so much more than just pull debris out. I have a very large skimmer for my tank size. Sure, it pulls stuff out of the tank that my corals could be eating but it is removed from the system so its not rotting somewhere causing nitrates or phosphates to rise.

The canister I used years ago was a fluval 407 one of the cheaper ones they make not the fx series. That can was on a 40b for the most part and it would go to frag swaps to provide flow in my small acrylic frag tank that I would set up. The 40b had 2 fish and every inch of rock was covered in zoanthids. The 2 fish was a demon orchid dottyback and the only fish it would not try to kill a mandarin. When I would go to a frag swap I would turn off the canister and take it with me once I returned I would put it back on the tank. I probably didnt open it for 3 or 4 years when I did I was amazed at all the worms, pods and sponge growing in it. I only opened it because the pump died. The only thing in it was the main assembly that directed flow, it was difficult to remove it because of all the sponge growing on it and the walls. The rocks came out in one big chunk stuck together from sponge. I was kicking myself for disturbing it as I tried to trans plant the sponge in my massive sump but it died off. I am sure the worms and pods I was able to remove were perfectly happy in their new home but all that cool sponge was not. I just remembered, the hob CPR fuge/skimmer was also on this tank. The 40b ran lower numbers than my main reef probably for many reasons but I fed the tank daily spot feeding the zoas so there was a lot of food going into the tank. The only time there was bare rock in the tank was when I had pulled a zoa covered rock out to frag.
 

zwalter38

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I currently run my 135g mixed reef tank on two fluval fx4 canisters with no issues. The tank has been up for 2 years. I dont often clean them either to be honest. However I do have a display refugium plumbed into my system so that helps remove the nitrates. I honestly struggle to keep nitrates and phosphates.

All that to be said. With the right maintenance, canisters can most definitely run successful saltwater tanks.
 

Subsea

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I was considering a canister filter for my marine aquarium instead of building a sump. But I was advised by my regular aquarium outlet that a canister filter is like a "nitrate factory". Despite that I explained that I planned to keep only two clownfish and later one sea anemone, I was advised that I will be better off to have sump.

Do you agree with the statemement that a canister filter is a "nitrate factory"? My tank is a 125 liters Juwel Rio 125.
Welcome to the adventure! I have been addicted for 55 yrs.

I do not agree that a canister filter is a nitrate factory. In my mature reef tanks I dose ammonia as a nitrogen source. I use canister filters as cryptic refugiums. Inoculate with reef rubble, no filter floss and no maintenance required.
 

Randy Holmes-Farley

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I was considering a canister filter for my marine aquarium instead of building a sump. But I was advised by my regular aquarium outlet that a canister filter is like a "nitrate factory". Despite that I explained that I planned to keep only two clownfish and later one sea anemone, I was advised that I will be better off to have sump.

Do you agree with the statemement that a canister filter is a "nitrate factory"? My tank is a 125 liters Juwel Rio 125.

It can be a nitrate factory. What exactly do you want it to accomplish?
 

bubble.of.zen

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I was considering a canister filter for my marine aquarium instead of building a sump. But I was advised by my regular aquarium outlet that a canister filter is like a "nitrate factory". Despite that I explained that I planned to keep only two clownfish and later one sea anemone, I was advised that I will be better off to have sump.

Do you agree with the statemement that a canister filter is a "nitrate factory"? My tank is a 125 liters Juwel Rio 125.
I just posted this in another forum, and thought I'd drop it in here too.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I love my fluval 307. I have a 36 gallon bow-front with no room in the matching stand for a sump. I feed heavily with a mandarin, firefish, blue chromis, clown, watchman goby, purple urchin, harlequin serpent star, softies and sponges. Before my canister I was running two 75 aquaclear hobs with a protein skimmer, and the noise was maddening. I bought the spray bar to go with the fluval and along with my hygger mini wave maker, I only need to do 5 gallon water changes every other week and clean the canister once monthly. I ended up removing the protein skimmer because my tank was running too clean. It took about 3 months for everything to balance out.
Best,
ZW
 

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