Canister Filter & High Nitrates

Will4VT

New member
I have a 65 gallon tank with about 50 pounds of live rock and 2 Fluval Canister filters. A 106 and a 206. My Nitrates are sky high but I think that was because of overfeeding, moving the tank and not cleaning the canister out for about a month.

Anyways I was wondering if anyone has any advice as far as should I put LR in one of the baskets, using purigen, chemipure, etc.

In the 206 I just have Foam pad, Filter bio media rings, carbon.
In the 106 I have Filter bio media rings, and carbon.


All other levels are good expect PH is a little low at around 8.0
 
Nothing wrong with using a canister per se, just be careful what you put in it. Bio media and sponges, floss, anything that traps detritus and breaks it down into NO3 by providing a home for bacteria will all cause issues. Even carbon left for a while can be a problem as bacteria will colonize it just like any other media.

If you are planning to run the canister filter on a reef tank, I'd eliminate the media all together and just use it for running carbon or other chemical media when needed. When it's not housing carbon etc., I'd just run it empty as a source of additional water movement - a spraybar attachment behind the rockwork is a great way to eliminate dead spots, for example.

A sump/refugium is a much better alternative, but if you've got a sumpless tank and want to make use of a canister that's gathering dust, I say go for it - just think of it as a large powerhead that lives under the tank
 
What would you recommend putting in it then. My tank is a FOWLR.

I have a question it may be dumb idk but... If I dont put the sponge, filter floss, etc then where does the detritus go if my filter is not cleaning it out of the water?
 
Are you doing anything to remove the nitrates? You've hit on two causes, overfeeding and neglecting to clean the mechanical filters, but another cause is inadequate nitrate export. Most common export is water changes, then there's macroalgae either in the DT or in a refugium, ATS, etc, etc. Skimmer will also help by removing the junk before it gets broken down to nitrate.

The quickest way to get that nitrate down is multiple large water changes. Just keep the water temp and salinity the same as your DT water, and the fish won't care about large water changes in a FOWLR tank. Vacuum the substrate and rocks while you are at it.
 
Ideally, a sump with refiugium and skimmer is the best choice. That being said, you can still run a sponge, filter floss, etc but you have to understand how much more maintenance is required to continually clean and ensure there is no food, dirt, waste, etc. The cause of your problems with the high Nitrates is because the canister filter doesn't properly break down any of the organic food and waste It basically just stores it.

If I were you, I would get a skimmer and a sump at the very least. Having a sump could allow you to move some of the Liverock from the display tank to the sump (providing a little more swimming room for your fish, it would increase slightly the total volume of your tank, and it would allow you to house a skimmer.

If you are adamant on maintaining the Canister filter I would recommend doing more water changes, and more frequently cleaning your sponges, filter floss, etc.
 
Waiting on my salt I ordered to come in to do more water changes.. Ran out doing a water change and my LFS charges out the a$$ for the Instant Ocean Salt. I dont have a refugium or a skimmer.

I have been siphoning/ Vaccumming the rocks.
 
I have been siphoning/ Vaccumming the rocks.

That's a good start.... the problem is when you stir up the sand bed where do you think all the dirt, uneaten food and waste ends up? In your canister filter :rollface:

You need to be cleaning the canister filter a lot more if you want to stick with it and want to lower your nitrate problems.
 
I dont have the $ right now to buy a sump, refugium, all the plumbing that goes along with it, pumps, etc.

Can someone just recommend what I can do to lower them without buying a sump?

Shaginwagon13- I dont mind the maintenance. Should I just continue to clean them out about every 3-4 days and still run the sponges, bio-media rings, carbon?
 
I would rather it go there and me be able to remove it then have it decaying on the rock itself right?
 
I would rather it go there and me be able to remove it then have it decaying on the rock itself right?

Yes I would recommend you clean it every 2-3 days if possible because that is the source of the problem for your high nitrates.

You could also try maybe some hermit crabs or cleaner shrimp inside the display tank. They love to eat uneaten food, they could help you out a little.
 
i ran a fluval 205 for a while on my 33. never had drastic issues, but did have nitrates like crazy. I only ran purigen or carbon. Absolutely avoid any type of foam or bio media like bio balls. Only run mech media (filter floss, filter pad) if you have particulate in your water after a water change. Even then, remove it within 24 hours.

I eventually went to an HOB penguin with only purigen and got much better results. Even still, im building my sump setup tomorrow. The only real way to get that prestine water and reef growth is to bite the bullet and go to a sump setup with fuge and skimmer.

Also, cut back on feeding if your feeding alot. I only feed every other day.

Canisters on Reef tanks are just a glorified powerhead. I learned the hard way by trying to be stubburn, and the pros were right... Canisters never really work out for salt tanks.

Youd be suprised at how much junk can get caught in those ribbed fluval hoses.
 
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Thanks stlcard... did you take out the 4 sponges that are in the red thing?

My tank is just a FOWLR right now tho and I dont plan on converting it to a reef tank.
 
I dont have the $ right now to buy a sump, refugium, all the plumbing that goes along with it, pumps, etc.

Can someone just recommend what I can do to lower them without buying a sump?

Shaginwagon13- I dont mind the maintenance. Should I just continue to clean them out about every 3-4 days and still run the sponges, bio-media rings, carbon?

I wouldn't bother with the purigen and chemipure for high nitrate.

I used to run a fluval 405, and I still use it for QT. Here's what I suggest you do.

Rinse out the sponges very well, squeeze repeatedly until it runs clear. You can use RODI if you want, but I usually use plain tap water. You should do this at least once a week as a matter of routine, but you can do it more frequently for now until your nitrates are under control.

Check your ceramic biomedia ring trays. They should look dirty as a general rule, and that is normal since they are coated with beneficial bacteria, but there should be no large pieces of solidified debris. If there is solidified junk, rinse the tray in salt water, not fresh water, until clear. Do not be too aggressive here, as you don't want to wash off too much of the good bacteria.

Holw old is the carbon in your trays? If they are more than a month old, they go biologic and are also detritus traps. If they are more than a month old, replace them.

Sorry to say, but the quickest way to get that nitrate down is by water changes, You can talk to your LFS, and see if he can give you a discount on the IO salt. I suggest doing a series of 50% water changes twice a week until your nitrates are down.

Siphon the substrate and rocks when you do the water change. Invest in that contraption designed to siphon the substrate. This way, all the junk you siphon is taken out of the tank and discarded.

Later on, when your nitrates are down, you can look into getting more flow across your rocks, getting a skimmer and a refugium (you can do HOB) and maybe removing the ceramic rings for long term nitrate control. Start planning on a sump with refugium and skimmer, and get rid of the cannisters altogether when you have the $$$.

You don't have to go too crazy. You say you have a FOWLR and nitrates are not such a big issue with this type tank. BTW what's your current nitrate level, and do you have problems with algae or cyano?
 
Thanks Palting that helped a lot.

I've already order the IO Salt along with some other stuff thursday so I should have it buy Tuesday or Wednesday. I have 2 Korilas in the tank now. I have which model since I bought the tank of craigslist and the lady had no clue.

I am thinking about doing a DIY aquaclear refugium that a lot of people have been doing and had good results with.

I have been brainstorming some ideas about a sump and all and would probably sell the canister filters if I do for the money.

My nitrate level is 110ppm.

When I bought the tank and moved it my tank had a little cycle and had a small issue with some cyano but turned the lights off for 3 days and everything has been good. I have some brown algae trying to grow on the glass that I clean off every 2 days or so but no huge algae problems.
 
yes, take out all the sponges you can. they just trap your uneaten food, snail crap, algae and etc. Then they sit inside that dark canister with great flow and creates an orgy if you will for nitrates. Shagin is correct, that they WILL also suck up sand, even if you dont stir it that much.

I also did not have money for a sump setup (till now), so i worked with the canisters and purigen only. Then i move to an old Penguin 330 HOB (hang on back) power filter that i had from my freshwater days. Ive SUCCESSFULLY been using the HOB with purigen in one side, and Cheato Algae and live rubble rock in the other. I slide in a filter sponge after a water change or when i stir things up to catch the big junk that would normally pass over purigen. But remove it within 8 hours.

If your going to stick with canisters heres my opinion and recommendation. take it with a grain of salt:

- First, back off on feeding. (every other day is what i do, flake with brine or dry pellet, Frozen stuff like phytoplankton and mysis is more what i call an occasional "treat") It may not seem like you are overfeeding, but more times than not we are. Its fun to watch and fatten them up, but its more difficult to battle poor water chem in the long run. Most Detrius comes from you. and your feeding. If you limit the buffet, you limit the crap.

- Your going to have to water change often (maybe 10-12 days about 10%). Mix a batch of salted (RO/DI if you can) water up the night before and let it agitate over night with a spare powerhead or air stones/ bubbler. RO water will limit the phosphates you add to the tank. Phosphates = algae = nitrates and a vicious cycle of dying algae and new algae. Plus, detoxed tap water still has other impurities and metal. (Think about your plumbing? and what all that water is running through before it comes out your faucet)

-clean that canister a minimum of every 4-5 days. 2-3 days better. This becomes a pain... eventually, most canister operators break down and find something different (HOB or sump), not because they are all lazy, but mostly because every time you stop that canister, gunk flies out into the tank, you agitate the tank, fish are stressed = more poop, and you fire that thing back up and more gunk flies out.
** side note, im more convinced the majority of nitrate issues with canisters are from debris gunking up inside those ribbed tubes. and from operators not flushing them everytime they clean the canister. (Like me)

- make sure you have great flow over your rock work. It needs to be chaotic and random, but not blasting your fish across the tank. (Better flow = more biological filtering with your live rock and "good" bacteria). Waves in the ocean provide chaotic flow across rock work, add oxy to the water, and helps agitate the detrius from settling.

-Massive amounts of nitrate not only creates issues for fish, but it creates issues for the "good bacteria" you want to keep. It also limits coraline growth and over all ability to biologically filter the nitrates the way nature does in the reefs.

-even good bacteria eventually dies. more so if your water chem is off. So once they die, thats adding more problems to your tank. (I dose Seachem Stability 4mL with each new batch of water change). Just in case the bacteria in my live rock need some reinforcements.

-The most important thing i think i have learned is let that darn tank settle. Constantly changing things, moving things, cleaning things creates chaos. Its an ecosystem, it has to settle and balance out. think about the badass tanks on this site... how big they are... how many devices they have operating it... skimmers, GFOs, sumps, refugiums, automated lighting, auto wavemakers. While expensive, they also completely operate themselves which means the ecosystem can settle out.

My biggest mistake as a newb, (still consider myself that, compared to the other old dogs on RC) was constantly sticking my hand in the tank to fiddle, clean, meddle, test, and poke around.

Sorry for the rant. hah.
 
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id recommend you not use ceramic bio media. They seem to be an oldschool trend that is phasing out. People propose they create more harm than good (by trapping detrius). Besides, your LR and LS are plenty large enough for bacteria colonies.
 
stlcard- no ranting at all thanks a bunch for the info.

I 100% agree with you about the ribbed tubes on the filters. I cleaned my canister out today and when I started it back up it shot so much gunk into the tank. I think tomorrow I am going to clean those out tomorrow.

Any tips on how to clean them out mine is about 3 1/2 foot long
 
stlcard- no ranting at all thanks a bunch for the info.

I 100% agree with you about the ribbed tubes on the filters. I cleaned my canister out today and when I started it back up it shot so much gunk into the tank. I think tomorrow I am going to clean those out tomorrow.

Any tips on how to clean them out mine is about 3 1/2 foot long

I blow the crud into my tank when it starts back up, I just have a fish net in front of the return nuzzle to catch all the crap that comes out. Ha Ha!

I would do a extra large water change , like 80% or more, that should put a huge dent in your nitrates. Then it's on you to maintain/clean the canister sponges every few days if your gonna run it with them.
Feed less, do more water changes, clean your filter more often. If you still struggle then you have to many fish or bioload.
 
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