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FAQs about Canister, Cartridge Filters For Marine Systems, Rationale/Use

Related Articles: Physical FiltrationReview of the ViaAqua Canister Filter

Related FAQs: Canister Filters 1, Canister Filters 2, Canister Filters 3, Outside Power Filters& FAQs on: Placement, Media, Plumbing, Maintenance, Troubleshooting/Repair, By Manufacturer: Eheim, Fluval, Other Brands,

Canister, cartridge type filters are useful as mechanical, and to a degree biological adjuncts for otherwise well-set-up and maintained (and other-filtered) marine systems

Fluval Canister Filter (Chemical Filtration Use) – 08/02/12
Hello crew,
<<Hey Ed>>
I just added a CPR Aquafuge 2 HOB refugium with live rock, miracle mud and Chaetomorpha to my 30 gallon display tank which houses live rock, live sand, a couple fish and some soft corals. I am still running a Fluval 305 canister filter with three trays and of course the filter pads. I would like to do away with the filter pads and just keep it for the extra bio load and for water circulation.
<<Okay…and maybe chemical filtration?>>
I would like to run Neo Zeo, Reef Carbon and Seachem Matrix instead in the canister filter.
<<Ah! Okay…>>
My question is, in what trays would I place them?
<<I don’t think it makes much difference here…though one consideration might be to put the “most expensive” product in the last tray to process water in the hopes of extending the period between replacement [grin]>>
I have an upper, middle and lower tray in which each tray has to compartments?
Is this effective?
<<Will remain to be seen…but likely of some use, yes>>
And am I on the right track?
<<I do think chemical filtration is a useful adjunct…and a canister filter is an excellent method of application re>>
Thank you,
<<Happy to share… EricR>>

Flow Rate -- 09/25/09
<<Hiya Rod'¦no need to be quite so formal, mate>>
In your responses you state that the water turnover should be 4 to 6 times the tank size.
<<Hmm, have you corresponded on this with someone previously? Do please include prior related correspondence with your submissions so we can refer them to the appropriate crew member. But to get back to your statement'¦ There are no hard and fast rules re water flow in aquaria. Like so many other factors, it to needs to be tailored to the occupants>>
I have a 75 gal tank so flow should be over 300 gph, if I figured right.
<<Maybe so'¦not enough data here for me to give an informed reply>>
Then how is an Eheim 2215 with a flow of 165 gph supposed to be good for up to a 95gal tank?
<<This rating is for the 'filtering capacity' of this canister filter'¦and has nothing to do with whether it provides 'adequate flow' for any particular system>>
Do I really need 2 of them?
<<To filter a heavily stocked system'¦very possibly, yes. But if only more 'flow' is needed/desired, there are better methods/devices for this. Have you read here, and among the associated links (http://www.wetwebmedia.com/circmarart.htm)?>>
<<Happy to share'¦ EricR>

Flow Rate -- 09/25/09
Thanks for the quick response.
<<Quite welcome>>
Sorry for the lack of info. But that answered my question; they are looking at filtering capabilities not flow.
<<Ah'¦very good then>>
Keep up the good work.
<<We're trying>>
I use the planted advice all the time.
Thanks again,
<<Cheers, EricR>>

Canister Filter Questions: Eheim in a SW setup. 4/23/2009
<Hi Sherri.>
I just purchased an aquarium on Craig's list and got it home and now I need help.
I had a Oceanic Saltwater aquarium several years ago and I actually had a lot of luck with it and would like to try one again.
<Welcome back to the hobby.>
This aquarium is about 100 gal and it has the EHEIM Professional 2226 filter.
<An excellent filter when properly maintained.>
My question is can this filter be used for a Saltwater tank?
<It can be used for a saltwater tank provided it does not have the integrated heater.>
If so what other things do I need, like a Protein skimmer and what?
<You should definitely use a protein skimmer. Do read here:
http://www.wetwebmedia.com/proskimrart2.htm >
Any help at this point would be great and as I said I am familiar with the saltwater tank but I had the Oceanic where everything was built-in on the back of it...I looked at the EHEIM site and can not find if this filter can be used for Saltwater or if it is Freshwater only. If you know please let me know so I can get it set-up.
<It will be fine for saltwater. Do realize that while canister filters are useful for a saltwater setup, they do need more frequent maintenance - it will need to be cleaned every week to two weeks.>
<My pleasure>

Ocean Clear Filter/Use Or Not To Use 3/6/09 Good Morning Crew! <Good morning, Jeff> My question deals with a use of an Ocean Clear canister filter. I am replacing my current 120 gallon reef system that I purchased used, is horribly scratched, and terribly plumbed, for a new Oceanic System. I would like to keep things simple, as I am home often, and stick to routine water changes and maintenance religiously. I have been using an Ocean Clear canister filter on my current system, and would really like to eliminate it from my new system if possible, and advised. <OK> There are a couple of factors involved in my consideration of leaving the Ocean Clear out, as follows: If I use the Ocean Clear and a 30 gallon tank as a sump, the sump will have to sit kitty corner in the tank stand in order to fit the Ocean Clear. This makes it a bit more difficult to get at the father corner of the sump which is where the Refugium is located. I am quadriplegic, and require help in maintaining my system, so I like to keep things as efficient as possible. <Understandably.> What a good amount of sponge/filter media in the sump be sufficient, even though I would have to remove and clean it more often than I would the Ocean Clear? My other option is to use a 20 gallon long tank for a sump with no Refugium, that would leave me room for the Ocean Clear on the end as a 20 gallon long is 30". My feelings are that the larger the sump, the better. <Yes, more water in the system and capacity for unexpected shut downs.> Also, a Refugium built into the sump would be a plus, am I correct on this? <Would be a big plus.> I will greatly appreciate your expert advice. <The micron filter systems are great for sparkling clear water. On the other hand they need to be maintained at least weekly. If not, the trapped waste will soon elevate nitrate levels once decomposition starts. Cleaning isn't much fun as the filter needs to be soaked in a bleach/water mixture for 24 hours and then a rinsing and soaking in freshwater to make it safe for re-use. I would keep the 30 gallon sump and refugium and incorporate an efficient protein skimmer in the system if you are not already using one. You can use the sponge, but again, this will require weekly maintenance and would not be necessary if a protein skimmer is in use along with an ample clean up crew to tidy up. I do not use any mechanical filtering in my tank for the reasons stated above.> Thank you for your help, and the fantastic website. <You're welcome, Jeff, and thank you for your fine errorless writing. Is much appreciated. James (Salty Dog)> Jeff Castaldo

Canister Filter in a Reef 20g 12/8/08 Hi There, <Carlos.> I've been reading your site for years, it's a wealth of information. <Thank you.> My question is about canister filters in reef setups. I have a 20 gallon that had a wet dry with a bit of Seachem's Matrix. All was fine till I had some nice 150w MH so had to get rid of the wet dry and bought a canister filter. I added the Matrix I had to the new canister filter, included some Purigen and active carbon and a  week later added more Matrix totaling 1Kg. 2 weeks later my nitrate went from 20 to over 50. <...> I have been doing 30% water changes ever since but to no avail. <What does your change water read re nitrate?> I clean the entire canister filter every fortnight, and floss every week, should I just turn off the canister filter and run with just a pump in the tank or give it more time (7 weeks now)? <Do you have any other means of biofiltration, live rock perhaps?> I am not over feeding, in fact I've stopped feeding my corals to see if it helps. <The nitrate is coming from somewhere, feeding corals or fish, makeup water.> Any advice would be greatly appreciated Cheers, Carlos <Do write back regarding any other biomedia and your water tests on the change water. More info needed here. Scott V.>

Re: Canister Filter in a Reef 20g 12/9/08 Hi Scott, <Hello Carlos.> Thanks for your reply, <Welcome.> I have over 8 Kgs of premium live rock, nice and purple. <With this amount of LR in a 20 you certainly could remove the Matrix, it is likely just sitting there collecting detritus, not helping your nitrate issue.> To aid circulation I have 1 Tunze 6025 powerhead. My makeup water is from NSW from mid north coast of Australia, I tested it and it has 0 nitrates, my makeup water for evaporation has 0 nitrates as well and I add Prime to it. <Another possible source. While NSW has its benefits, it also has its risks. One of which is die off in the water itself. See: http://www.wetwebmedia.com/seawater.htm and the above links.> I also have a bit of Caulerpa in there to help with the nitrates. As a scientist my self, I am stumped :( Thanks once a again, Carlos <Welcome, Scott V.> Sorry forgot to mention, I add 2 smallish pieces of live rock in there 3 weeks after adding the canister filter, could this have caused this huge spike? <Certainly, yes. Depending on the point that these rocks were �procured�, this certainly could be the source.>

Re: Live Rock... actually canister filter use, SW  10/20/08 I also have a large Fluval FX5 external filter. What would you suggest I do with it. <Run it empty if you want, just water movement.> Should I fill it with filter media or use it with nothing in it for water movement. <They are a bit of maintenance nightmares, need to be cleaned often (weekly), so the less stuff to trap detritus the better.> Kenny <Chris>

Sump or Canister filter or both? 8/24/08 Hello again guys, I've been doing a lot of research lately and I'm feeling really stupid right now. When I started into the saltwater hobby I was evidently told all the wrong things. Ok, here we go. I have a 46g bow front with no sump, a BakPak 2 protein skimmer and a canister filter plus about 45 to 50 pounds of live rock and live sand for the substrate. I was told this is basically all I needed. DUH!!!. <This setup can be quite successful, not that bad.> I'm currently in the process of getting my newly acquired calcium reactor up and running but have decided to hold off until other problems are solved. First, I would like to know what I need exactly to get this thing right. Sump, canister filter or a wet/dry filter, or a combination? <If you wish to upgrade, a simple sump will do. This can house your reactor, skimmer, heater, etc. While you are at it, do consider incorporating a fishless macroalgae refugium, these can work wonders. No wet/dry needed, you rock takes care of that, the canister can be used for mechanical filtration and running carbon if you wish, but will need to be cleaned very frequently as to not allow detritus to accumulate, leading to nitrate production. Do also keep in mind that a sump/refugium can be something as simple as a $5 plastic bin or cheap 20 gallon aquarium, no need to spend several hundreds of dollars on acrylic unless you want to.> I eventually want to put corals in this system so I want the setup to be right. My canister filter is on its last legs and I've been pricing the Eheim pro's but if this type of filter is not good then I could easily spend the money on a sump or wet/dry and overflow box plus pumps and plumbing. <I would rather see you invest in a sump and overflow setup with this rather than another canister. Also, do consider drilling this tank for an overflow before you stock a bunch of corals in it!.> Please help this poor misguided fool! Craig <It sounds like you are on the right track, Scott V.>

Re: Sump or Canister filter or both? 8/24/08 Thank you for the quick response. <Welcome.> I have a few more questions though. I've read that the live rock shouldn't be placed directly on the LS due to trapping dangerous gases. This is how my current setup is. I would have to change it I know, but do I save the sand by vacuuming it very well or should I just replace it? Should I replace the LR as well or remove it and scrub it down and hope for the best? The rock should be raised up above the LS correct? Then just arrange the LS around the LR or leave the LS out all together and place the rock on the glass? <Hmmm, the only real danger comes if you wish to have digging critters in the tank. They can dig beneath a rock, leading to a rockslide in your tank. You may put the rock in your tank and then add the sand if you wish for your aquascaping to be more stable. Use the same rock and sand, no need to change.> As far as a sump goes, what needs to be in it besides a return pump? I know I can place the skimmer in it and the return line from the reactor but I've read that bio bale or balls are not good. <Nope, your live rock will provide biofiltration.> My protein skimmer has bale, should I remove it? <I would. This stuff is in there just as much to prevent microbubbles as anything. With the skimmer in your sump this should not be an issue. Also, do pay attention to the water level relative to the skimmer, this can make a huge difference.> Should carbon go into the sump or some kind of phosphate remover? <Carbon if you run it. Phosphate removers should be used with caution and water testing. It is easy to strip the water of phosphate, it is a required compound.> I've been searching around some sites looking for a sump and overflow boxes, what is your opinion on these? CPR CS50 300gph and the CPR CS90 600gph for the overflow and a Eshopps RS-75 10gal sump. <They will all work, use double what you will need incase one fails, likely in time one will. Also, plan on an actual flow of 300 gph per 1' bulkhead, this is the size these boxes typically use. Do consider the drilling I mentioned before, check out my site: Glass-Holes.com for more info.> I'm not sure what my flow rate should be for the sump so that's why I'm looking at two different overflow boxes. I've honestly thought about emptying the tank completely and take the fish to my LFS for safe keeping until I can get all this stuff cleared up, good idea or bad? <No, not really much to clear up.> This tank has been running for about 6 yrs. now as is. <If the status quo is working, maybe you don't want to touch it!> I'm in SC and there aren't any really good LFS's in this area where the info can be trusted. I have some books but they all approach a marine setup differently. The sump info and LR,LS info would really help me out in trying to figure out what to do. I love the site you all have and have found the information eye-opening, thank you again. Craig <All this is just a matter of reading through the WWM FAQs re overflows and plumbing. Doing so will shed much more light on the whole process. Welcome, Scott V.>

Re: Sump or Canister filter or both? 8/26/08 Hi again, o.k. you've sold me on the drilling idea because my airline to my skimmer gets clogged all the time. But how do I drill the tank with the fish still in it? <You don't, it will need to be emptied. Very much worth doing before you take the leap of adding corals.> Also, I'm not clear on the comment about the water level in relation to the skimmer in the sump. How do I get the water level right in the sump to prevent a flood if the power goes out? <There are many, many pages covering this. Start here: http://wetwebmedia.com/sumpdesfaq.htm and it will become clear.> As far as the LR and LS, I plan on removing both and place the rock on top of 2" dia. pvc cut to a 1" or 1-1/2" height to raise it off the floor of the tank and then adding the LS. Just not sure on the depth the LS should be. Sounds like a good idea? <Yes, this will be fine. As for the sand: http://www.wetwebmedia.com/dsbfaqs.htm .> This is a 46g. bow front tank so which overflow would I need? <An overflow that will handle the flow we discussed previously will do. Get one that will handle twice to flow (more drains) to have some redundancy; ideally two 1.5' drains.> Thanks again. The information here is golden. Craig <Welcome, keep reading, Scott V.>

Eheim Canister Flow Rate 8/1/08 Hi WWM Crew, <Krissy> I have been searching for some time for the answer to this question (I have even called Eheim directly). My question is how does Eheim calculate their listed flow rate for canister? <By measuring the flow, I know, had to say it!> I know most brands list their flow rates as what the max flow will be if the canister was empty and ran without media. It seems to me that Eheim has lower flow rates than other brands but still lists them as able to handle larger capacity aquariums. For ex: Marineland c-series 360 is rated at 360 gph and recommended for up to 100 gallon tanks. Eheim pro II 2126 lists a flow rate of 250 gph but is still recommended for 100 gallon aquariums. Is Eheim more accurate at listing the flow rate in a real world situation (i.e. filled with media)? <I personally cannot speak to the method Eheim uses to rate their flow capacity. But, there are two points worth mentioning regarding this. First, Eheim is known for making the best of the best canister filters for good reason, they work great, extremely reliable and user friendly. Second, do not confuse flow rate with filtering capacity. A 250 gph flow is plenty to filter a 100 gallon aquarium. The ratings have many other factors, such as media capacity and effectiveness.> Thanks for the help! Krissy <Welcome, I hope this gives you some insight. I have used many canisters over the years, Eheim products being a fav. Scott V.>

Should I continue to use my canister filter? 7/8/08 Hi crew, <Hello> It seems I send you a question once a week now, but you seem to be one of the few reliable resources available. I have a 55 gallon reef tank, with a canister filter, AquaC Remora Protein Skimmer (recently purchased, maybe a month ago), about 50 pounds of live rock, and an approx. 1.5 inch sand bed. I test my water weekly, and I can never seem to get my nitrates and phosphates to zero. I do a 10% weekly water change and I used phosphate drops to control the PO4. <Better to find the source of the phosphates than try to chemically treat it after the fact.> I was speaking with an experienced reefer last night and mentioned that I was using a canister filter. He said that this may be the cause of my high nitrate and phosphate levels, stating that if I don't clean my filter media every few months, that the filter will continue to pump through the scum on the media, therefore releasing nitrates and phosphates back into the tank. <Less so with the phosphates than nitrates, but they can be problematic. Also to counter this the filter needs to be cleaned weekly.> He said with a 55 gallon tank, the Remora and my live rock are the only filtration devices that I need. He suggested getting rid of the canister filter. This guy has an AMAZING 120 gallon reef tank, and a 110 gallon reef tank with all SPS coral, calcium reactor, dual overflows...the works...so I think he knows what he is talking about. Though I haven't been in the hobby for very long, I was under the impression that I needed a filter on my tank. <Not really, unless you have a high bioload, otherwise the rock and skimmer should be sufficient.> What do you guys suggest? <You could remove it, just be ready with water changes if any parameters gets out of line, it may take a little while for the bacteria in the rock to compensate for the loss of the canister. Or you could just remove all the filter media and continue to use it for water movement and occasional carbon/poly-filters.> Thanks again, Jared S. <Welcome> <Chris>

Re: Should I continue to use my canister filter? 7/8/08 Chris, <Hello> Thanks for the information. <Welcome> I think I will go the route of removing the media to maintain water flow. And I should keep the carbon and poly-filters in the filter at all times? Or place them in occasionally? Thanks again, Jared S. <I would run only as needed, otherwise you will have the same problem as now and need to clean them weekly, which can be a maintenance headache.> <Chris>

User friendly canister filter and bristleworm control 02/25/2008 Hi Guys: What a wonderful website!!! My question is regarding user friendly canister filters. I'm a bit confused. <<G'Morning, Andrew today>> I have a 55 gallon marine tank with Emperor 400 Bio Wheel, powerhead and CPR Back Pack protein skimmer (your recommendation; thanks so much, love it!!). Have about 70 lbs. of live rock, in addition to crushed coral and base rock. Livestock: (one of each) false percula clown, royal Gramma, striped damsel and a wrasse that eats bristleworms. <<Maybe consider switching out the crushed coral at some point for reef grade sugar sized aragonite sand>> The present equipment keeps aquarium fairly clean between bi-weekly, 20% water changes. Water is clear but never polished. Why is this? Bristleworms? Insufficient filtration? <<Switch water changes to 10% per week, rather than the larger change every two weeks. The bristleworms won't cause dirty water>> Would like to put "water polishing" filter on to really sparkle up the water. Questions: 1. Can I use a canister filter in addition to present equipment? <<Yes, you can do that, and run some carbon in the filter to hopefully clear up the water>> 2. What is you recommendation for a simple user friendly canister filter? What size, brand, model do you recommend for this set up? Keep in mind my mechanical skills are extremely limited. (The CPR BakPak PS is just super!! I need something as efficient and easy to maintain as this). <<The Rena XP2 filter would be a fine choice ( http://www.marinedepot.com/ps_ViewItem~idProduct~AP7313.html ). These are easy to use with tray filtration. You can add a bag of carbon to one of the trays and live rock rubble to the other>> 3. Need bristleworm control tips in addition to the wrasse which does a decent job but does not eliminate them completely. Is this possible? <<If your bristle worms are not at plague levels, then they are fine to leave in there. They will act as part of your cleanup crew in the tank>> Looked at the Marineland Magnum 350 and Eheim models of canister filters but am not sure which would be appropriate. Would the HOT Magnum 250 do the job? Do you recommend HOT, immersible, or undertank models? <<the marine land is not a very adaptable filter besides running the standard sponge filter, which is not really much use to you....same again with the cheaper Eheim filters, they are just sponge filter pads.. The Rena Xp2 or 3 would be a far better choice>> Please advise. Thanks so much!! June Mary <<Thanks for the questions. Hope this helps. A Nixon>>

Canister Filter... media, SW    2/14/08 Hi everyone and thanks for all your past help! My tank spec is as follows; 280 litre tank, 1 inch bed of fine crushed coral sand, good selection of nice live rock, few mushrooms, star polyps,1 lemon peel angelfish, 2 clownfish, 1 scooter blenny, 1 fuzzy dwarf lionfish, 1 regal tang ( larger tank on way as promised by wife! ), <For the Scooter Blenny's sake also.> 1 fire shrimp, 1 purple reef lobster, I run a Fluval 405 external filter, Hydor 300 watt external heater, red sea Prizm deluxe skimmer ( next thing on list to upgrade after a lot of sucking up to wife ha ha ), <Good plan.> Arcadia over tank Lumminaire t5 lights, Tunze Nanostream Turbelle 6045 powerhead ( was running 2 of these but kicked up to much sand , just so powerful ). <These do provide tons of flow and must be directed carefully.> All livestock happily getting on and all seem to be very healthy, eating and active. I have read somewhere recently that the external filter I use is actually only any good to use for ROWAphos and carbon? <Canisters can be used for mechanical/biological filtration also, they just require frequent cleaning to prevent detritus buildup which leads to excessive nitrate production. You refer to your substrate as sand, but if it is the typical coarsely crushed coral substrate, then same applies to it as the canister filter.> Do you think this is right? Would my tank crash if I didn't use the external filter with all the sponges and filter media ( bio rings ) or would my live rock be able to cope? <This depends entirely on how much live rock you have. For a tank this size I would look to have a minimum of 50lbs (23kg) for filtration.> Thanks for your time and expertise, hope to hear from you soon. <Welcome, I have included some pertinent links below, Scott V.> http://wetwebmedia.com/marcanfiltuse.htm http://wetwebmedia.com/marsubstsel3.htm

Fluval Died...Replacement Recommendation 1/29/08 Hi there. Grateful for all your insights and answers. <Hi Walt, happy to help out.> Hope you can get specific on our situation. Have a 150 gallon tank with a TruVu Platinum series sump. Only inhabitants are a 7 inch Porcupine Puffer and a 3 inch Dog Faced Puffer. Our nitrate levels have been quite high for awhile, and while the fish are healthy, we're trying to 'improve' conditions. <OK, better water quality never hurts.> Recently got rid of the wet/dry bio-balls and put in a refugium with biosediment, rock, sand, Chaeto, and turtle grass. <Nice.> Have an Aqua C Urchin Pro skimmer (got this because of the small footprint size in the left part of the sump...9x9) <Good skimmer.> Our Fluval 404 canister filter just stopped working (5 years old, transferred it from a 55 gallon). So now the question.... Get a new, better, filter - and if so, a recommendation please..... (Marineland, Eheim, etc) <I would have to vote for the Eheim.> OR just upgrade to a super skimmer (footprint issue a concern) and forget the canister filter approach. <This really depends on the amount of live rock you have in this system. If your canister was providing your primary biofiltration you should act quickly to replace it. If you have sufficient live rock, you can skip the canister altogether. As far as skimmer choices, I would rather keep the skimmer you have over the model proposed. If you wish to upgrade (not a bad idea), perhaps another Urchin or something in AquaC's EV series. Both will be tight, but should fit in your sump area of 9'x9' (do account for the addition of the pump required with the EVs when measuring things out). The EV series can even sit outside the sump if you have room.> THANK YOU!!! Walt

Re: Fluval Died...Replacement Recommendation 1/29/08 Thank you very much for the quick response, as we weren't sure how 'urgent' a priority replacing the Fluval was. <If it were your primary biomedia, yes.> With approximately 100 pounds of live rock in the 150 tank, perhaps we'll see how the levels are before rushing out to get a new canister filter. <You have plenty for your stated bioload.> (I believe I read on WWM that some canisters can be nitrate 'houses', which really defeats our goal of lowering the levels...would that be true of even an Eheim?) <Yes it is, if it is not cleaned very frequently.> AND...If we decide to go with just the live rock approach rather than an Eheim canister, do we need even more live rock in the tank? <You could put a little more in a 150, but you will be fine here.> THANKS again! Walt <Welcome, best of luck, Scott V.>

Should I Use A Canister Filter? - 12/31/07 Hi Eric or whoever is on duty this evening, <<Hiya Ken...Eric here>> My 90 gallon SPS tank is doing great. <<Excellent>> I recently set up a second tank primarily for a RBTA and a pair of Clarkii clown fish. <<Neat!>> I will probably add another 4 small fish and some star polyps and mushrooms at some point. <<Mmm, too bad...the tank/anemone would fare much better in the long term without the polyps and mushrooms trying to constantly poison it>> The tank is a 46 gallon bow (3 foot length) with about 65 pounds of live rock, TEK 5 T5 lighting, two Tunze 6025 Nano Stream powerheads, and a Deltec hang on back skimmer. I am not using a sump. Even though I can make a large % water change with a couple of buckets of new water, or water from my SPS tank with this size tank if I ever run into trouble, I was wondering if I should add a canister filter to my set up? <<I would...for chemical filtration (carbon/Poly-Filter)>> If I did this, I would not use the bio media or noodles, and just use the sponge for mechanical filtration to trap debris. <<If you do...be sure to clean the filter sponge of detritus one or more times a week, else the canister filter will become more of a "problem" than a "solution">> I could also use it for PhosBan etc if needed. <<Indeed>> I have no mechanical filtration in my SPS tank, but the debris eventually will end up in my sump which I can then clean out. <<Agreed... And with good strong water flow, the suspended detritus (or marine snow, if you like) is actually quite good "food" for your corals>> This tank has no sump. I of course will have a clean up crew for the tank. Do you think the canister filter is a good idea or a waste of money? <<Can be quite useful, as described/when maintained properly>> If it is a good idea, is Eheim still the way to go? <<Many choices available these days...but you won't go wrong with the Eheim product>> Thanks, Ken <<Happy to help. EricR>>

Re: Should I Use A Canister Filter? -- 01/02/08 Hi Eric, <<Hello Ken>> Happy New Year! I hope all is well with you. <<And a 'Happy New Year' to you as well!>> I may opt out of the mushrooms and polyps then. <<Will be best'¦in my opinion>> I did not realize that they "poison" the water. <<Mmm, yes'¦quite noxious. And as with everything on a reef, are constantly 'at battle' for the available real estate utilizing their quite formidable chemical weaponry. A fact that is compounded by the confines of an aquarium>> I though the issue was with the anemone moving around and stinging its tank mates. <<This too can be/is a problem. But in this scenario, it is more likely the anemone would eventually succumb to the stress and strain of defending itself from the encroaching polyps and mushrooms as they reproduce and spread. These organisms are quite popular with new aquarists for their ease of keeping, colors, and prolific nature'¦but I can tell you, many (including myself) regret their introduction>> If you recall, I did plan on a BTA in my 90 gal tank but took it out after a couple of months. BTA became a PITA. :) <<Does happen>> One last thing about the canister filter, would using a PhosBan filter with RowaPhos be as good a solution as using an "Eheim" type filter? I know they are completely different but if I do not use the canister for mechanical filtration, Rowa Phos would probably be all that I would put in the chamber anyway. <<There may be some difference in the degree of efficiency between a canister filter and these fluidized reactors, but yes, for what you describe this is fine>> IF, this tank runs as my 90 gallon does, I won't use carbon or anything else. I only use the PhosBan reactor and no other media on my 90. <<I see>> What is your opinion? <<I say, give it a go>> I haven't spoken to you in about a year (when my tank was set up initially) <<Ah yes'¦I believe I was in Hawaii visiting/diving with Bob at the time>> so let me give you an update. <<Okay>> If you recall, it is a 90 gallon tank with an H&S skimmer, Marine Technical Concepts Pro-Cal calcium reactor, Sunlight Supply Maristar light fixture with two 250-watt 10,000k Ushio bulbs and two 54-watt T5 ATI bulbs, and two Tunze 6000 powerheads with controller. The tank did not start out as an SPS tank, but that is basically what it became. I literally have my SPS growing like weeds. <<Neat!>> I can keep my alkalinity constantly between 10 and 11 dKH. My calcium is about 420 but I really don't check it that often as I really just monitor alkalinity. <<Would seem that calcium reactor is working well>> My nitrates and phosphates are very close to zero using a Salifert test kit. I think my skimmer gets the credit for that as I do not do a lot of water changes. <<Likely so'¦but do consider the water changes also replenish the good/remove the bad things we don't/can't test for'¦or even know about, or understand their role/effect. Everything in your tank is a consumer of the elements in saltwater, as well as a polluter of this medium. Nothing has a larger impact on replenishing the one and diluting the other than frequent water changes'¦ Something that should never be neglected in my book'¦regardless of how 'efficient' the filtration gear or how well we 'think' our tank is doing>> It was great hearing from you. <<And you, mate!>> I'm glad you're still here. <<Ah, well'¦I'll likely continue for as long as Bob sees benefit from my participation [grin]>> Regards, Ken <<Be chatting. Eric Russell>>

R2: Should I Use A Canister Filter? - 01/02/08 Hi Eric, <<Ken>> You have a good memory. <<I wish'¦ [grin]>> We were exchanging email at that time you were diving in Hawaii. <<Yup>> You are correct about the water changes in that it is not just about diluting what is in the tank, but also what gets brought back in. I do notice after a water change, some of my coral are more open. <<Mmm, yes'¦but which aspect is the cause re? Dilution of pollution? Re-supply of essential elements? Both? Likely the latter I think> I have one last question regarding my new tank that has recently cycled. <<Okay>> When I use a turkey baster to blow off the rocks, there is a lot of debris. <<Indeed'¦detritus/mulm>> Since I have no mechanical filtration or sump, I was thinking of briefly using my diatom filter that I used to use when I had a plant tank and use it on this tank while I blow off the rocks and the debris is suspended in the water. <<You could'¦ Or simply siphon it away when doing FREQUENT WATER CHANGES [big grin]>> It is a Tetra or Whisper and it worked quite well. Is there any harm using the diatom powder? This may be a dumb question but can I get diatoms in the tank from this? <<While the powder does have a very high silica content, I think there is little to be concerned with considering the short duration of use involved. Do be sure to keep the powder itself from entering the tank>> Thanks and regards, Ken <<Happy to assist. EricR>>

"Polishing" Water  12/24/07 Dear Crew, Happy holidays! <And Happy Holidays to you, too! Scott F. in today!> I need your help yet again. I want to clarify my water more. I have an Outer Orbit light fixture and the light seems to reflect every particle in the water. I was thinking of adding an additional filter, but not sure which one. I was thinking of either an Eheim where I can pack my own filter media, or an Ocean Clear inline filter made just for polishing water. If I go with the Eheim, I don't know what filter media to use. I would prefer the Eheim as this will only draw 50 watts. Any suggestions? Thank you. Jeff <Well, Jeff- I like the Eheim, too. I would probably use a mechanical media, such as "Ehfimech", which is a porous clay material that traps debris. I would also utilize activated carbon for its chemical filtration capabilities. If you pay attention to the replacement and cleaning of these media, you'll get really great results for the long run. Best of luck to you! Regards, Scott F.>

External Canister filter 11/26/07 Hi <Hello> My set up is 190 Liter 42g, (UK) bow front, air driven skimmer, LR (but unsure how much (see pic, please note one or two small pieces of base rock at the bottom). Filtration is via an Eheim pro 2 2026- media- some sort of white ring in the bottom compartment, covered with a blue coarse sponge, then a layer of white/cream porous balls in the next and a bag of phos remover next to it. <OK> All parameters low, but I've been advised remove all media and have the Eheim solely for mechanical filtration. I'm diligent when it comes to maintenance, and I intend to clean the filter, propeller (gunk), and the media once a month (using tank water when doing a change), therefore shall I stick with my set up, or remove the media? Mo <The problem you are hearing about is with the mechanical filtration itself. It traps detritus that could otherwise be processed out of your system, producing excessive nitrate. The filter and media can be used if you are very diligent about cleaning, I would clean it at least once a week. Just keep an eye on your nitrate level and watch out for the dreaded algae. Happy reefing, Scott V.>

Why Add A Canister Filter With A Wet-Dry? -- 11/07/07 Hello guys and thank you for donating to me some of your time. <<Quite welcome>> In an e-mail that was sent to me from Eric R., he answered some of my questions regarding my high-nitrates (has recently gone down to 25 from over 160 ppm) <<Excellent>> and also gave me a few general tips. <<I hope they were of use>> It was suggested by Eric to buy a refugium and also a small canister filter with cut-up Poly-Filter in it to better my setup. <<Indeed...both are always worthwhile additions in my opinion>> I understand why I should have a refugium (a medium Aquafuge refugium and live sand is coming in the mail), but I didn't understand why I would need a small canister filter plus I don't want to buy one if it won't be worth my while. <<The canister filter was suggested merely as a means to provide some additional chemical filtration to your system...if you have some other way of utilizing the Poly-Filter media then by all means do so>> Maybe I was unclear when describing my setup. Oh, and FYI I've only been in the marine hobby for 3.5 months so I am of little knowledge. <<You are changing that just by reading/being here>> I have a 120g FOWLR saltwater tank with 45lbs live rock with a 2" layer of crushed coral. <<I probably mentioned this before, but this two-inch 'crushed coral' bed is probably a large contributor to your Nitrate issue as the course material will trap much uneaten food/detritus and the depth is not sufficient to foster enough of the right kinds of bacteria to function as a proper DSB. It would be best to either reduce the depth to an inch or less...increase the depth to four-inches or more...or change it out for a 'sugar-fine' Aragonite material>> It houses a Snowflake Eel, 4 Damsels, and various Hermit Crabs and snails. For filtration I use a Little Giant water pump that runs 640 gph into a 2' wide by 1' deep by 1' high wet-dry trickle. The water when going through the middle chamber in the wet-dry trickles first goes thru a standard filter pad, then thru De-nitrate and activated Carbon, then thru a piece of felt, then thru more De-nitrate and activated Carbon plus Chemi-pure, then thru another filter plan, and finally trickles over live rock before being pumped into the main tank. I have a Berlin Triple Pass Turbo Hang-On Protein Skimmer that is rated for tanks up to 250g. I now realized I made a poor purchase regarding my skimmer but I'm not about to replace it due to the fact it cost over $200. I also have 3 foot-long air stones lining the back of my tank for extra oxygen for my Snowflake. <<The skimmer should oxygenate the water well enough...as I suspect the air stones are creating much salt-creep around the top of your tank>> Considering my current setup, would it be a good idea to add a canister filter? If so, why, and how big? <<A canister filter would ensure the most efficient/effective use of the Poly-Filter just by the very nature of its design/function (forces water 'through' the filter material), and any of the small 'external' canister filters would suffice...but...you can also likely employ the Poly-Filter material somewhere in your Wet-Dry filter... Is up to you>> Thank you for your generous service. -Phil <<Happy to assist. Eric Russell>>

Giant Hawkfish problem... Actually induced env. prob.s   9/3/07 Hi, <Christine> I have looked up your site for a while now but now I am having trouble with my giant hawkfish and I hope someone is able to help me. I have had him for about a year and in the last month I have switched from a sump system to a canister filter... <Mmmm... I am not a fan by and large of using these types as sole...> it is a Rena xp4 and the tank size is 100 gallons. He shares it with an eel (fimbriated) and since i switched the sump out i noticed his breathing got a lot heavier. <Oh yes... very likely the agitation of air/water in the sump brought oxygen into high saturation> I thought it was the heat so I got a chiller, still the breathing was heavy although the temperature is perfect so I got some aeration going in the tank. For about a few weeks he was fine but as of the last few days I noticed his breathing has gotten very heavy, lethargic and occasionally does this scary coughing thing where he looks like he might explode. <Very dangerous... Very likely these two species/specimens also need more room than this 100... I have seen Fimbriated morays that required hundreds of gallons for themselves> I did a full battery of tests and found the nitrate and nitrite to be both high.. <How high is high, sigh...> I did a 20% water change added some AmQuel + and so far the readings have been perfect. <Warning! This Kordon product (the PVP ingredient) will give false negatives with some test kits...> Everything is at zero. Although the ph is a bit low at 7.8. <Too low...> Anyway, that's all the info i think that might help... i will be adding another biological filtration unit to the tank with a few days in hopes that it needs more (as he and his brother are messy eaters) but i just don't know what might be wrong. <The loss of the sump... not enough volume... the too-driven-nitrification effects of canister filtration, poor water quality... You've stated it all> I will also get proper ph to up the ph level to 8.2. <Not a good idea, means... need more naturally available carbonate, bicarbonate... more hard, soluble substrate/s...> The eel seems to breathe heavy at times but it seems the hawkfish is the one who is losing his color, breathing heavy at times and then almost not at other times and occasionally coughs. Sorry if this is long but i don't know what it might be.. any thoughts? Parasite maybe and if so how does one tell? I don't want to add anything to the water that might make them worse... thanks so much for any feedback! Oh and also the salinity is perfect as well as the temperature so those are not possible problems. thanks!!! :) Christine <... Please... get a larger system, bring back the sump, consider using the canister simply as a contactor... Please read here: http://www.wetwebmedia.com/marcanfiltuse.htm and the linked files above. Bob Fenner>

Re: 30 gallon aquarium with Eheim 2234  7/28/07 Bob, <Hubert> Thanks for your reply. I guess I need to do some additional research on fish/system compatibility. After reading few books I had the peaceful community tank figured out.:-). Also, I know that there is no media in the skimmer, but what I was referring to was the type of media in my Eheim filter that would be best in conjunction with the Remora skimmer. <Is as stated previously> So if the live rock provides great bio filtration, skimmer is removing all <Not all> the nasties from the water, should my filter media (Eheim) focus on mechanical/chemical filtration only. Or should I also use bio filtration in the Eheim as well. Thanks!! <In most all marine applications I suggest canister filters only as adjuncts to bio-filtration, with the chance of occasional chemical filtrants. This is all archived/posted on WWM> Hubert <BobF>

Use of Canister Filters, SW, Koran Sys., Selecting a/the "truth"   -- 06/07/07 Guys, I found this on FAQ http://www.wetwebmedia.com/marcanistfltfaqs.htm, . You said to read about the systems and such, Bob said the FX5 canister filter might not be a good choice and I have too many incompatible fish in my small 80 gal tank, but... <Yes> Under Canister filters, the FAQ says they can be good for bio filtration. <Can... in actual practice the use of canisters period has some dire potential... should the power or pump go out for a period of time... an hour or more let's say... and resume... the anaerobic activity can be troublesome... to deadly> The FX5 I'm using is about the largest in the industry, strictly bio only, and is easy to clean if necessary. <Good features, points> Using additional filtration for mech/chem and a skimmer (of which I just purchased a larger one), by reading some of this FAQ it looks good. The question answered below makes mention of the other filtration besides the canister needing to be addressed but doesn't dissuade the writer from using them. <Antoine's opinion at the time...> Secondly, the writer has a 55gal with similar bioload, that being a Koran angel, a yellow tang, a moon wrasse (thinking Lunare wrasse or similar), plus some others. There is no mention of concern about incompatibility or bio overload for the tank size. <Again... I certainly would mention... Please, not to be argumentative here, take a look around reference works re Pomacanthus...> I'm adding another 25 gallons with the 80 gallon, plus with the designs to go to a 135 in the very near future. <Still too small for this species...> Now, the shark is pretty stationary (and currently only 6", but yes, will grow), and yes the puffer creates a bigger bioload on the tank. But the three large fish (not large yet in the 80, larger with time in the 135), that being the doggy, the tang, and an angel, ought to be similar to gentleman's livestock below and there was no concern mentioned in this FAQ. <Again... keep reading. Selecting one input from a small sample is not going to grant you much insight... Yes, even if it were mine> A Koran gets pretty large, too, and in a 55gal? <Yes> See, I did go back and reread the FAQ on compatibility of the three fish, and with the yellow tangs didn't see where there was a direct conflict. Angels can be aggressive, yes. Some actually recommend puffers as good tank mates with these fish, too. Just stressing again that the below question was an example and isn't my original Q. Two, I am in NO WAY being critical of any WWM answer, as you guys have been really helpful to me, but I just wanted to point out that sometimes when I do reread the previous stuff I get some conflicting info. Below quoted from FAQ on Canister filters: "Re: Filter change Hi all- Thank you for the reply to my filter question. As a follow-up, will switching from a hang-on filter to a canister make a significant difference? <most canister filters are larger than hang-ons and may very well be more effective by virtue of their size. Pick a good brand like Eheim that has been around for decades and is tried and true> I am currently running a 55 gallon saltwater aquarium with about 30 pound of live rock, a CPR Bak Pak skimmer, an undergravel filter, and a Whisper hang on filter. Basically, it's a FOWLR (plus one starfish) with a Cardinalfish, Koran angel, yellow tang, two striped damsels, and moon wrasse. <hmmm... do maintain that UG filter diligently> The biggest reason for my considering a filter change is the frequency with which I'm changing the filter pads, sometimes twice a week. <either you are feeding WAY too much food or your skimmer has not been adjusted to collect good skimmate DAILY or a combination of both. A canister filter is not going to solve your problem... only put a bandage on a symptom> I know a canister filter requires maintenance as well, but I wonder if I'm harming water quality by having a filter with less filtering ability (although water parameters test fine). <if you get the canister, do modify with a course foam block (like from a Hagen AquaClear filter) on the intake strainer. Rinse and reuse this frequently and this will dramatically extend the life of the media in your canister> Thanks in advance for all your help. All good wishes, Daryl Klopp <best regards, Anthony>" <Please read here: http://www.wetwebmedia.com/marine/fishes/angels/pomacanthus/koran.htm and the linked files above. BobF>

Canister or Power Filter for Nutrient Export? Neither   3/15/07 Hi Crew.., <Hello.> I have a 55 gal reef tank with about 35 lbs of live rock, an A-Miracle HOT wet/dry trickle filter and a remora protein skimmer and two extra pumps just to increase water flow. Inhabitants are 10 Nassarius snails, a serpent star, mushroom, a few button polyps, diamond goby, flame angel , a bicolor pseudo and an algae blenny. Nothing terribly fancy as you can see. Mostly, things run well,  but whenever I seek to add a fish, I start having problems. I think the wet/dry  is too small, and as a result, the system cannot handle even a slightly  increased bio load. I'd like to add supplemental filtration, and I am  considering the Eheim Pro 2224 canister. What do you think? <For nutrient control, no.> Should I use it as both chemical and mechanical filtration, or, given that its just to be a supplemental, am I better off just with chemical filtration to keep nitrates and phosphate <Nice to have on hand in emergencies, use if you are keeping noxious inverts....but necessary to run it all the time? No.> s in check? Any suggestions on using carbon in this scenario? Will adding such supplemental filtration allow for a slightly heavier bio load? <No, use more water changes and/or refugiums for this.> I'm not looking to over do it. I just want to add maybe 2 fish and perhaps some hermits, maybe another mushroom. Thanks!! I love the  site!! <Honestly what you need is better nutrient export. I wouldn't recommend a canister or a power filter for any for any of this. Look up Hang on Refugiums...refugiums in general....on WWM. Adam J.> Marine Filtration Problems/Options  2/5/07 Hi, <Hey Mark.> Thanks for the great site. <Welcome.> My question is about filtration. <Okay.> I recently  added  a canister filter to my 125 gallon tank in a attempt to up grade my system only to realize that this is not really a good option. <Correct.> I was considering removing all the filters and media and placing live rock in the  baskets. But it feels like a waste of electricity to run it at all. <Well if you have LR in the display'¦.not necessary, I would just keep it empty, use it to run chemical media/carbon when necessary.> I do not  have a sump and all my equipment is in the main display. Is it enough filtration  to just run a good hang on protein skimmer with live rock and power  heads for water movement and if so how important is the depth of the sand bed, I  currently have 1 inch. <Well what type of skimmer is it? Most hang on skimmers can not handle such a large aquarium'¦Look into adding refugia.> My fish are a juv. blue angel, juv. sailfin tang a juv.  Naso tang and pair of black and white percula clowns. Also, I change  10%  of the water weekly. Best regards, Mark <To you as well, Adam J.>

SW, placement of ancillary canister filter for chemical media use Greetings guys from sunny South Africa trust you are all well, thanks for the great site and great advice. A quick question please I am currently upgrading my entire set up and adding a 100 Litre sump / refugium  to my 400 Litre tank . I am currently using a small 50 litre sump with a bag of activated carbon, my question is that I have a Fluval filter that I am not using and want to add this directly to my main display tank system but primary just use it for my activated carbon. <Okay> Would you recommend this? <Mmm, not a bad idea, use> Will that not be a bad thing for my refugium as it will suck up all the beneficial creatures? <Likely not suck many up... some will come to live in it> Your advice would be greatly appreciated.   Werner Schoeman <I would rig this canister filter up to run water into and out of your main tank itself. Bob Fenner> To Canister or Not to Canister? 7/18/05 That is the question! <"Whether it be nobler in the mind to suffer the slings and arrows of outrageous water changes..."> Thank you in advance for any guidance you can provide. I've learned so much from your site since locating it several months ago.  I started with a 55 gal. FOWLR last Aug. then purchased a stocked 125 gal. in April of this year with the intent of upgrading and transferring most of my 55 into the 125.  I currently have approx. 150-200lb. of LR, a AquaC Remora Pro (no sump), a Whisper power filter with Chemi-pure, and four Maxi-jet 1200's for water movement.  Livestock includes a mated pair of false Perculas, Yellow Tang, Naso Tang (I know he will eventually outgrow--came with the 125 tank), Royal Gramma, Coral Beauty, Mandarin Dragonet, assorted snails and a few hermit crabs, Button Polyps, Finger Leather Coral, and Green Star polyps. I do not wish to do a full reef and will not be adding anything for a while.  I do not have room for a sump at this time and have been considering an Eheim 2028 or 2250 canister filter to replace the Whisper--mainly for mechanical/chemical filtration and increased circulation.  Would you recommend doing this? <Mmm, am a huge fan of Eheim in general, their canister filters (and pumps) in particular, but I would opt to add another large hang on filter here actually... the canister would be nice in that it's quiet, efficient in biological and mechanical filtration, but they're a pain to service on most marine systems... and can cause troubles if not serviced quite often (like weekly)> My nitrates are 0 and I understand canister filters can raise this--does this still occur if I don't use their biological material? <Mmm, there are other media that can be used to discount overdriven nitrification> Any recommendations you can give are much appreciated! Diana Miller <You have mine here, and all of outs on WWM. Bob Fenner>

Re: Beginner Seahorse Tank, on resolving conflicting advice on Canisters  10/5/05 Bob, Leslie, thank you both for your time and advice on my previous email.  I've taken your advice, did more research, and have taken the plunge! <Welcome> I set up a 37G, foregoing the Nanocube.  I have about 1/3 volume in Live Rock, Remora Pro skimmer with Mag3 pump.  I got the live rock from the LFS, "mostly cured" in their words.  I have a small AquaClear 20 powerhead to supplement flow, at about half capacity. According to my research and belief, the Remora should be returning about 100 gph to the tank, and my powerhead approx 60-70 gph, I think.  Was aiming for about 170-180. (37x5=185).  For the seahorses to come.... I hope you can help me with the following. (1)  My guy at the LFS has been pushing me to get a Canister.  I want some mechanical filter to hold carbon, and to filter particles.  But it seems some people on WWM say LR and skimmer is enough and canisters are more negative (nitrate?) than positive.  I'm worried about inconvenience of cleaning.  On the other hand, the added water volume and carbon would be desirable, I think.  Which way should I go?  Canister? Powerfilter? <I would use the latter myself... easier, cheaper to run, acquire... and does all the two can/will do> Is Eheim 2215 too much flow for the seahorses?  I have read bigger is better, here on WWM on canisters.    <Could, would work... has a discharge spray bar....> But I'm worried about too much flow.  The LFS guy says point the water return down and I can limit influence on the flow.  Or should I just ditch the entire idea and leave it with LR and skimmer? <Up to you. Can be added later if you want> (2)  It's been about a week since I set it up, and the water is doing great (ph.8.1, ammonia 0, nitrite 0, nitrate 10mg/l, spg 1.024, Ca 430).  but today, I noticed a lot of the LR is starting to turn/grown rusty/orange/brown on the edges.  It does not look like the pictures of BGalgae or Cyano I see on the FAQ here.  No wispy hairs, just looks like... rusty fuzz.  Is this natural? <Yes> or should I be concerned? <Re? Read on WWM re... cycling, LR curing... Cyano... this latter is what this mainly is>   Even the rock that has great purple coralline when I got it, is starting to turn "rusty" on the edges.  On the other hand, I think there is at least a little pimple of orange sponge growing on another piece of rock that wasn't there a few days ago. (3)  My RemoraPro is foaming, but not enough to reach the container.    Do you think this is because I have nothing in the tank and there is genuinely little to skim, or because I have to tweak and skim more?   <Maybe a bit of both> The skimmer has been running for 3 days now.  I have the prefilter foam on the Mag.  Should I not have this attached? <Time for the requisite "stop obsessing" stmt. here> (4)  So far all I have in my tank is the LR, live sand, and water.  I thought cycling would take longer, but last three days, I have not had any ammonia or nitrite.  Am I missing something?  Did I miss the cycling somehow?  I can't decide what to add first - snails, etc., or some macro algae for seahorses to hitch onto (looking ahead).    Caulerpa seems to be the most available around here, and looks like something seahorses would enjoy hitching onto.  But the advice on them also seem to be both extremes - easy, not easy.  risk or crash.    not in the main tank (I don't have a refugium).  Should I get something else?  or is it ok to get Caulerpa?  Should I stick with fake plants and synthetic corals for hitching posts? <I would for now> I am getting a bit nervous and excited to have it all set up.  Thanks for your help in advance! Hiro <Bob Fenner> Filter-less   1/30/06 Hi, After my last water change, I decided to unplug my Fluval and see if the tank can get along without it. I have a 55 gallon tank with a remora C skimmer, 3 power heads that together turn over approximately 700gph. I do 5% water changes weekly. I've recently noticed a lot of  brown particles on the surface of the water. I can't think of any reason for this but the elimination of the Fluval, which by the way only had carbon in it. I would be interested in your thoughts.............. Thank you <Canister filters can be of use in many types of marine set-ups, but the use described here is better served by simply placing the chemical filtrant in a Dacron bag in the water flow path somewhere. I would add some mechanical/particulate filtration however. Bob Fenner>

Canister Filter vs. Wet-Dry Filter   3/20/06 Hello, <Hi Joe - Tim answering your question today!> I have racked my brain researching what filter I should get for my 75 gallon tank. I plan to have a fish only saltwater tank with no invertebrates. Despite the internet research, the 4 books I've read and the local fish stores - I can't decide. The wet-dry seems to be the best, but at double the price. The canister seems to be the economical choice but will it be enough? The research I have done leads me to believe that a fish only tank will be ok with a canister filter but if I add invertebrates then I'll need a wet-dry filter. Please let me know how far off I am. <Joe - please read this and the links on this page for all the information that you seek http://www.wetwebmedia.com/marine/setup/filtration/marineFiltr.htm > Should I get a protein skimmer too? <You should definitely get a protein skimmer, irrespective of whether you opt for a fish only or full reef system. Do research skimmers before making your purchase as there are considerable differences in quality with correspondingly minor differences only in price!> Thank you in advance for you time. < Always a pleasure - I do hope that I have been of some help!> Respectfully, - Joe Canister vs. Refugium...And Winna' by TKO in the First round is - 03/09/2006 Hi Bob, <Josh actually, but hello just the same.> I was reading some FAQ yesterday and noticed that in a particular question you recommended the removal of a canister filter to assist denitrification. I was wondering if you could give me your opinion of whether I should swap my canister filter for a refugium containing Chaetomorpha algae. <I'd say absolutely.> My specifications are: 850 Litre tank; Wet/dry mini reef with Skimmer, Eheim 2218 Canister filter. <Did you just say wet/dry? Hmm...may be the answer to your question.> My nitrates are too high. About 40-50ppm, and this is what I am aiming to reduce. <And rightly so. I'd look into removing both the wet/dry and canister here (eventually). Are you using LR? How much? You can plan this system to take care of itself, with diligence on your part.> So what will I lose/gain by doing this? <All posted...repeatedly.> Thanks Joe. <I know it's not definitive, but so it goes. Your help lies in understanding/embracing a filtration methodology. It becomes easier as you read about each. Remember...don't buy the cup holder if you don't need it. - Josh>

Canister poss. addn. to a F and anemone WLR   5/9/06 Hi Crew - I have a couple of questions for you today.  First, some useful info: I have a mixed reef 74gal reef ready oceanic tank with a 30gal sump. I have converted both holes in the overflow box to drains and have return via hard PVC from the opposite corner of the tank.  I am using a LARGE Iwaki MD70RLT for the return (I know this may be "too much flow") operating at about 6 feet head pressure.  The return pump also runs a skimmer and a chiller.  I have over 100lbs of LR.  My tank is about 2-3 years old and has been relatively trouble free until recently.  NO3 levels are below 10ppm, NO2 and ammonia are ~0.  My phosphate test kit reads zero. Problem/Question 1: I recently upgraded to this larger pump and because the flow through the sump is so high, it is hard to keep filter floss in place (as you might expect).  I am stuck with this pump however and rather like the flow in the tank.  However, I have recently had my first algae explosion which I think is due to inadequate particulate filtration. <And likely the "natural" aging of your hard substrates, loss of "bio-diversity"... Please search, read on WWM re... I would switch out a bit of the substrate and LR> I use RO/DI water always, feed very little (a small cube every 3 days or so), replace light bulbs fairly frequently (pc), and do frequent (enough) water changes. So now, I am considering adding a canister filter inline between the return pump and tank (after protein skimmer) to help remove some of the particulate matter.  I plan to clean the filter weekly/biweekly with water changes.  Can you recommend a quality canister that can accommodate this type of flow and pressure? <There are a few... a fave is the "Nu-Clear" line... for their size, decent engineering, flexibility... though still a pain to open, keep clean...> Also, do you see any major problems with this thinking, so long as filter is cleaned frequently - other recommendations?   <... a few... diverting some part of the water flow into a "closed-loop", getting a larger sump, re-orienting/baffling the present flow/doing away with the floss and making the sump more into a refugium... with concomitant modifications there> Problem 2 which may/may not be associated with above problem:  I have recently been noticing that I am losing Turbo snails like crazy.  I have a number of Turbos and Astraea.  The astrea seem to be doing ok, but I keep finding dead Turbos.  The only thing that I can think of is that I have recently begun using a pH buffer as my pH is always hovering around 7.9 due to DI/RO use.   <Mix these adjuncts in with the new water, well in advance of its use> I have never been a fan of additives but thought my tank may appreciate the higher pH (although, I have never noticed any problems over the last 3 years with the lower pH).  I don't keep hard corals, so I have never worried about Ca levels.  Could reduced Ca levels due to increasing alkalinity be causing this? <Yes> Since raising the pH, I have a bubble tip anemone that I have had for years that is now much smaller and not expanding its tentacles nor eating.  Hence, I have stopped using the additive and noticed that the tentacles seem to be much longer and it is eating again. All other inverts and fish seem to be fine - minus the snails.  I know I'm probably missing something. Sorry for the length, and always - thank you for your great help! Peter <Thank you for writing so clearly, thoroughly. As mentioned, do change out part of the hard substrates, mix supplements in with the change water in advance. I do suspect that a good deal of your issues here are resultant from a loss of both ready biomineral reserve (from the substrates becoming less soluble based in their exposure, make-up), and the reactionary use of the buffer. I would read through the sections on WWM re Refugiums, make modifications to the present or additional sump, and not likely add a canister filter mechanism here. Too much flow restriction, maintenance/induced troubles likely. Bob Fenner> Ammonia Spike After Power Outage.. canister filter danger   7/2/06 Hi, <Hello there> Thank you for your excellent site.  I'm a former fresh water hobbyist turned salt water since Oct. of last year.  Your site has been a huge help in the last year.  I have always found ample information without having to write but have experienced my first major problem.  I was hoping for a second opinion on my plan of action to deal with this.  My livestock include one sailfin tang (I know he'll need a bigger tank and will provide for him), 2 clarkii clowns (mated pair), one blue damsel, one red knobbed starfish, one banded serpent star (a brown w/ darker brown striped brittle star not sure if that's the correct name as I've never found his exact pic on your site), <There are many such species> 3 blue legged hermits, a cleaner shrimp, and live rock with various little hitchhikers. I have a 72 gallon, hex tank, that has been running for almost 9 months.  It cycled well last year and I thought that I had made it through the flooding in the area that had shut the power off several times without trouble.  I discovered this morning I was wrong.  My ammonia level was slightly elevated (normally it is 0, nitrite, and nitrate zero, pH 8.2, temp around 72) this morning it was 0.25 ppm for ammonia.  I found out my magnum 350 was the problem. <For other readers this is a canister filter... would "go anaerobic" with cessation of power/flow> Although it had come back on after the power returned it wasn't primed and therefore never was really working.  Like I said I'm a beginner since my fresh water always had hang on whisper filters. <And these are hang-on power filters... open to the air> So now I know that I've got to check that when the power goes off.  I got the 350 running, but stupid me over looked that the little water left in the intake and return ubing had gone bad.  It caused my ammonia to spike to 1.0 ppm. I was horrified. So I added the recommended dose of ammo-lock 2 as an emergency stop gap after doing a 25% water change.  I plan to do another 25%water change in two days.   <Any ammonia will hopefully be gone before this> I will also stop by the LFS to pick up some stress zyme to add after the next water change.  I thought that that may offer some help to replace any bacteria harmed from this large a disturbance in the cycle (I had vacuumed the sand, changed out some of the decor, and changed out the filter media before I turned on the filter and sent that horrible water into the tank). <Yes, best to vent initially...> I will continue to test and do changes as needed to keep the ammonia, etc in control.  Does this seem a good plan? <Yes... though, as stated, likely all will be rectified in short order on its own>   I had been planning to add some more live rock, would now be a good time to do so? <Not for a few weeks> I feel like an idiot for not realizing the filter wasn't moving water and then letting that water into the tank. <Happens... a common mistake.> Soon after I set the tank up my father was diagnosed with cancer and ten days later my father in law had a heart attack.  Things are only starting to get back to normal so I'm not as observant as I should be with the tank. <Good that you recognize these influences, events... Even better that you are able to keep all in perspective. In a/the grand course of things, the aquarium is "small potatoes"... Put emphasis where emphasis lies> Sorry for the long email, I was trying to give all the needed info.  Thanks for all the help and hard work. -Ali <Thank you for sharing. Bob Fenner> DSB Canister Filter? - 07/24/06 Hello, <<Howdy>> I just started the fish keeping hobby and I established a 90 gallon reef tank in my living room. <<neat!>> While doing research I came across the process of denitrification. <<Okay>> I came to understand that Nitrate filters are not reliable. <<Mmm, probably not so much "not reliable" as "fiddly"...requiring constant attention/adjustment to optimize their usage>> Instead, I read that a DSB could be very effective at reducing Nitrates. <<Indeed>> Well the thing is, I don't want to add a deep layer of sand in my display tank, and since I can't get a sump (there's no space under the tank) I came up with an idea that might seem weird: Could I apply a thick layer of sand in an empty canister filter to act as a DSB filter? <<Mmm, no...aside from not being a large enough volume to be of benefit, pressurizing/running the filter will cause the water to be "forced" through the entire volume of sand. This will defeat the denitrification process as there will be no "stratification" of the sand bed with the varying levels of oxygen allowing the different classes of bacteria to form/populate...all of which are part of/necessary to the process of denitrification>> I imagine it will fulfill the role of a sump. <<Not in my opinion>> Please correct me if I'm wrong. <<Since a sump is out of the question, you might wish to look in to the addition of a "hang-on" style refugium in which to place the sand bed.  Another option would be if you have room "over" the tank to place a large (salt) bucket half-full of sand with water pumped up to the bucket and allowed to gravity drain back to the tank from a bulkhead fitting placed just below the lip of the bucket>> Also, I live next to the sea, where the sand in the coastal areas is extra-fine (which I read is preferable for DBS).  Could I use this sand? or is it a bad idea? <<Best not to use it due to the possibility of introducing pollutants/pests>> One last question.  Concerning macroalgae, how effective are they at denitrification? <<Not so much "denitrification...is a different type of host/environment, performs a different function from the deep sand bed...yet still useful through regular harvesting for removal of organic compounds (including nitrate) as part of their nutrient uptake>> Also is there a problem to add those in my display tank (I'm particularly interested in red macroalgae)? <<Can be done, though some species can be very invasive (e.g. - Caulerpa sp.) while others might be quickly consumed (e.g. - Gracilaria) by some fish species (e.g. - Tangs/Rabbitfish) Sorry for the long read. <<No worries mate>> Any help will be greatly appreciated. <<I hope I have>> Thank you. Mohammad <<Regards, EricR>>

Filter dilemma... Lions and canisters, no my!   8/24/06 Hi there! I've been asking lots of questions and every time your answers were more than helpful, thank you so much! I have a filter question this time... I am planning to set up a tank for a Lionfish (Pterois radiata). It's a 65 gal, <Will be too small...> I already have the tank, the lights, etc. Actually, I only need the filter to start the whole thing. I know that Lions need a damn good filtration, so I was wondering, what filter should I use? There are so many choices, and not enough info... <Lots of both available> I was looking at these two models, but if you have any other suggestions for this kind of setup, it would be more than appreciated... anyway, there are the two choices I have for the moment: - Pentair Aquatics canister filters (separate units, one mechanical, on chemical...) <Nah...> - Eheim Professionel II (more expensive, but I heard that it's a good choice...) <Is better, but not the route I would go either... Canisters aren't generally "appropriate technology" for marine systems...> I'm quite confused, and I'd really appreciate some help here! Thank you very much!! BTW, the Radiata will be the only fish in the tank... Merci infiniment! Ivan <... Please read here: http://www.wetwebmedia.com/marcanistfltfaqs.htm and here: http://www.wetwebmedia.com/lionsysfaqs.htm and the linked files above. Bob Fenner>

- Filter Media - hello to all, <Greetings, JasonC here...> As I've read through thousands of your very very helpful FAQs, I see that it is mentioned that the bio material in wet/dry's are the cause for a nitrate factory.  I am currently running a Fluval 404 on my salt-going to reef-tank and I'm running those little BioMax cylinders and active carbon.  Would it be a wise move to remove the bio-material and just run carbon and poly filter in my canister filter? <Not using this canister filter, no. If a full-blown reef is what you want to do, it would be wiser to consider entirely new filtration gear to replace the Eheim.> I've got a 65g, w/ 60lbs of liverock and protein skimmer. <Might be time for a sump/refugium.> Thanks, Jason Surfs up! <Cheers, J -- >

Eheim filters (and saltwater filtration) Hi I have a 72 gallon tank with two damsels, a Prizm pro 300 protein skimmer, a power head and a Fluval 304.I noticed that my nitrates were a surprising 100 so I called my LFS last week and they told me that my Fluval wasn't good enough for my 72 so I bought a Eheim 2217 with the nitrate removing media and I noticed that you don't really support canister filters. Do you think that the Eheim will bring down my nitrates because I really want to try an emperor angel that I've had my eye on for quite some time now. thank you <Mmm, well, I really like Eheim products in general, and do use their canister filters (on my freshwater tanks)... But for a tank of this size and type, you'd be better of revisiting your options and brands. I would upgrade your skimmer... and look into other filter modes. Please read here: http://www.wetwebmedia.com/marine/setup/filtration/marineFiltr.htm and on... and on! through the many FAQs and article files linked (in blue, at top). See you in a while. Bob Fenner>

Supplemental Filters Dear Bob and Staff, I stir things up a bit on the live rock with a turkey baster about once a week. A lot of debris flies around during the process. My question is since I am only running a wet/dry filter with two overflows. Would it be wise to buy a canister or diatom filter and maybe use it once a week to pull floating debris out of the tank instead of hoping it will make its way to the overflows? <Hello Jim.  Yes, it would be a good idea.  I use a Magnum HOT for this purpose.  It is versatile in that you can use the micron cartridge for water polishing, or the media canister for whatever. James (Salty Dog) Thank you! Wet Dry Filter, actually... canister I currently have a wet dry filter setup on a 150 gallon saltwater tank. It is one of the systems that you need to start the intake yourself by siphoning water through the tubes.  Anyway my question is this, can I switch over to a Canister filter?  They seem to be much quieter and easier to manage. A friend of mine has a very nice saltwater setup in his office and he has an Eheim canister filter.  I only bought the wet/dry because the salesperson told me that's what I needed. My wet dry has been set up for about 8 months now.. Can I switch to a canister filter?  If so what kind would you recommend and what do I need to do to switch without affecting my fish?  <There are few canister filters out there (regardless of claims) that can effectively handle a tank that large. You don't mention the use of live rock so the wet/dry is a must for denitrification. The wet/dry also does a very good job in exchanging gas/oxygen with the water. As far as easier to manage, the wet/dry in my opinion is easier. Canister filters do need to be cleaned weekly with new filtering pad replacement. James (Salty Dog)> Thank You

100 gallon tank, mainly filtration... Tank goal: To keep corals, mushrooms, Caulerpa, and slightly delicate fish like angels, etc. Yes Bob, I have a little more than 500 pc watts to keep those corals and algae growing. <Okay> I have bought a 100 gallon tank which has been sitting around for several weeks but I just can't decide on what type of filtration to use. I thought I had it all figured out but every fish store I go to disagrees with my idea.  <As long as you agree with yourself... that's all that matters> I am planning to use an Eheim 2060 (500gph) with a large skimmer and plenty of live rock (60-80 lbs). If I ever find a simple, easy to understand sump system I may at sometime in the future add a sump but that probably will not happen immediately unless you think it is a necessity.  <Good attitude... or at least we're in agreement> Four sales people at different shops and even Petwarehouse have all said "Get a wet dry" but I don't want the added problems that are cataloged on your website. <A sump is a sump... you don't need a wet-dry... I wonder how much money these folks might make by selling such off the shelf systems...?> These sales people insist that the Eheim won't be enough filtration because: 1) it won't turn the tank over as many times as I will need for a quasi-reef/fish tank, <The live rock is/will be the primary filter...> 2) gph on canisters decrease every day the canister is used so the gph is constantly decreasing,  <Not so much with a properly packed Eheim... I speak from decades of using them> 3) one canister will only take the water from one end of the tank therefore not cycling as much overall water is needed, and other similar complaints.  <Uh, the tank only has two ends... and you can/should use submersible pumps, powerheads for more circulation, aeration...> I want a simple, low maintenance filtration system that is effective (performance and cost) as well as operating quietly and that will be difficult for me to misuse.  <Your insight astounds me!> Eheim with live rock and a good skimmer sounds like a winner to me but no one else seems to agree. <Umm, I do.> I have read lots of info and at this point and have resigned myself to taking whatever your suggestions) is. <My advice is, of course to only let only your conscience be your guide... You're on the/a correct path my friend. Bob Fenner> Thanks once again, David Dowless

Adding another tank Hello again Mr. Fenner, My brother-(who I brought into this great hobby/lifestyle) is remodeling his house & getting a 180 gal tank for his house & I'm jealous! <We should start a club> So, now I'm considering another 50g to set on the other side of my new Sony 55 digital TV.  <Wowzah! I'm tired of squinting at our thirty inch fossil cathode-ray type!> My existing tank is a 50 w/2 Fluval 304's & think I will set up the new tank the same way as the existing. My question is, can I use one of the existing Fluvals along w/some of the live rock & sand the shorten or eliminate the cycle process??? <Absolutely> I would buy 2 new Fluvals and use one in the existing tank and one in the new. What do you think? <Sounds good> My brother is actually coming to Las Vegas this weekend & we are going for all you can eat sushi sat night, you are welcome to join us. <Ah, no alligator tears for me, will be diving, photographing in the Bahamas> I'll stop tempting you after this. <Wanna bet?> If you are ever in Tustin, ca., definitely stop at a sushi bar called Tommy's-I have people here in L.V. that make trips to so cal to eat there. Thanx again for your assistance. <And you for yours. Bob Fenner>

Re: Adding another tank Mr. Fenner, I live in L.V., I don't bet! If my brother talks me into a room divider 150 or 180, can I still use the Fluval, sand & rock to kick start the system?  <Yes> I would probably go w/an under stand system, drilled thru the bottom & not have canister type filter. Can I still use the "macaroni" from my Fluval? <Yes> Have a terrific time in the Bahamas and Thanx again. If you go to Tommy's, have a Galaxy Roll. The best. Chat w/you soon Craig <Yum! Bob Fenner>

Canister filter question Dear Bob, <You got Steven pro today.> I love your website, it has been a great help in learning how to set up my saltwater tank. My tank has been going for about six months. It is a 12 gallon tank (one of the ones from Eclipse) that I have taken the hood off of and put a power compact light and a glass top for better lighting on. I have about 18-20lbs of live rock and about an inch of live sand as a substrate. I wanted to add a protein skimmer so I bought the Prizm skimmer as I read on your site that it was a good one for a small tank. I have a few polyps and one medium mushroom. I also have two clown fish that are fairly small. My levels are pretty good pH 8.1, nitrite 0, nitrate 10, ammonia 0, alkalinity 4meq/l, KH 12 and I add the standard trace elements Kalkwasser, strontium, coral vital, iodine. My question is that now that I have the protein skimmer I have to get rid of my filter that was hanging off the back of the tank because I have run out of room. A friend of mine said he would give me his Eheim professional II 2026 and all I would need to do is buy the substrate for the inside. This is a good canister filter that would solve my space problem, but is it too much for my small tank? In the next year I would like to move my small tank into a larger tank (probably a 30 or 50 gallon) so I thought this would be a good filter to grow with. Next question, should I use all of the recommended substrates (Ehfisubstrat, Ehfimech, 3pads) so that it becomes a biological filter in addition to my live rock? I asked at a store and they said that usually in a small tank you would change the pads every 2 months and every 6 months you should rinse the substrates in salt water. He said that it was okay to let most of your bacteria go to the filter and that in the end this would be beneficial for the tank. Does this all sound correct to you? <I have a suggestion for you that is going to sound weird, but it is what I would do. I would get the Eheim and not put any media in it. Your 12 gallon tank is pretty small to start with. Once you added the rock and sand, it probably only has about 8 gallons of water in it. You are not thinking of adding any more fish than your two clowns, are you? I would use the Eheim for additional circulation (~250 gph) and water holding capacity (maybe a gallon). Your rock and sand will provide you with enough bacterial surface area for your two fish.> Thanks for your help. -Pete <You are welcome. -Steven Pro>

Eheim 2213 can I use an Eheim 2213 to filter a marine tank. I own one and it is the ultimate fresh water filter, I would think it would be just as good at filtering saltwater, I am converting my 55 gallon and I have in tank canister and Eheim canister. there is more than enough water turnover, or is my Eheim useless. <not useless at all... a very fine filter that can indeed be used as your primary in a marine system...but not the only filter. Some live rock and/or a secondary mechanical filter will be necessary and give you great peace of mind with your investment in the magically beautiful marine animals. My very strong advice is to add as much live rock as you can afford. It is so efficient as a source of filtration that in some cases it can actually outperform and replace your Eheim. Still keep the Eheim for carbon and gross filtration> thanks Sam <best regards, Anthony>

Re: Filter change Hi all- Thank you for the reply to my filter question. As a follow-up, will switching from a hang-on filter to a canister make a significant difference? <most canister filters are larger than hang-ons and may very well be more effective by virtue of their size. Pick a good brand like Eheim that has been around for decades and is tried and true> I am currently running a 55 gallon saltwater aquarium with about 30 pound of live rock, a CPR Bak Pak skimmer, an undergravel filter, and a Whisper hang on filter. Basically, it's a FOWLR (plus one starfish) with a Cardinalfish, Koran angel, yellow tang, two striped damsels, and moon wrasse. <hmmm... do maintain that UG filter diligently> The biggest reason for my considering a filter change is the frequency with which I'm changing the filter pads, sometimes twice a week.  <either you are feeding WAY too much food or your skimmer has not been adjusted to collect good skimmate DAILY or a combination of both. A canister filter is not going to solve your problem... only put a bandage on a symptom> I know a canister filter requires maintenance as well, but I wonder if I'm harming water quality by having a filter with less filtering ability (although water parameters test fine). <if you get the canister, do modify with a course foam block (like from a Hagen AquaClear filter) on the intake strainer. Rinse and reuse this frequently and this will dramatically extend the life of the media in your canister> Thanks in advance for all your help. All good wishes, Daryl Klopp <best regards, Anthony>

New saltwater setup Bob; I just happened upon your website today and am astounded not only by the fact that it is so comprehensive in information, but that you make yourself available for questions from newbies by myself. :-) I am grateful! <You are welcome my friend. Given a similar background and desires, you would likely do the same> At the risk of boring you to tears with simple newbie questions .... I've purchased and read your book, "The Conscientious Marine Aquarist," and have found it to be extremely useful. However, I'm a bit confused by the conflicting information I've read on the Internet (of course) regarding the usefulness of canister filters in marine aquaria. <Different strokes... canisters can be useful adjuncts... for added biological filtration, handy places to launch chemical filtrants... Not a "one item does it all" type of filtration however... and do have some drawbacks (tendency to clog, generate abundant nitrates... inconvenience of cleaning...> I'm about to set up my first saltwater tank, and have purchased the following, upon the advice of my LFS: Standard 55gal tank Fluval 404 canister filter SeaClone protein skimmer standard hood setup with 2 24" 15-watt Triton fluorescent tubes 40 lbs aragonite reef sand My intent is to begin with a fish-only-with-live-rock setup. After some time, I'll probably also add some hardy invertebrates. My LFS recommended that I fill the canister filter with biological filtration media, only. <One route to go> I've since read many disparaging comments on the Internet regarding canister filters being "nitrate factories," and I'm getting the impression that I may be better off upgrading my lighting and, after the nitrogen cycle has completed, removing the canister filter and having only the skimmer, and live rock for denitrification. <All valid points that might be instituted.> If I keep the canister filter, will my fish and invertebrates be doomed to unhealthy nitrate levels unless I do water changes on an incredibly frequent basis? <You'd be better off with a "sump type" filter arrangement.> Some people on the Internet even go so far as to state that a canister filter and live rock work at "cross-purposes" ... <Actually they're more complimentary... in simple terms of aerobic and anaerobic de/nitrification...> Any advice? <Plenty... at this juncture, do keep studying, evaluating this apparently conflicting information (you will find it actually is not so... much more like the real universe, things are better/worse "depending"...) until you can sort through your choices... Some substantial part of the fun and learning from involvement in our interests is the personal growth of discerning opinion and fact. You will see. Bob Fenner> Thank you for your time. - Dave Clark

Extra filter pump for Fluval 404 Hi Bob, My present filtering is done by a Fluval 404. My problem is I moved the Fluval behind a wall a way from the tank. Now my water flow is very low, due to the distance tank.  <Actually... practically speaking, this distant placement should make little difference (the pressure in the intake line should offset the "head" resistance in the discharge side... unless it's a very long way (tens of feet let's say) or you've reduced the tubing diameter... Do look for "kinks" in the line... restrictions through valving, filter media/packing, fittings (I would remove any "spray bars" for instance.> My question is I just purchased a Mag 7 to help the Fluval with pumping. Should I place the Mag before the Fluval or after. I also have a UV sterilizer after the Fluval. The Mag 7 is rated @ 700gph and the Fluval is much less. I don't want to damage the Mag or Fluval with this increase in pump volume. Any help would be great!! <I am very leery here of telling you to try and do something I myself would not do... If a centrifugal pump were added, it would be placed ahead of the restrictive filter (such pumps "push" by design, engineering, not "pull"... However there may be a real danger in "popping" the filter canister, O-ring... I would NOT add a pump here... Let's chat over some other possibilities... like adding a sump/refugium to your system and using the new pump there... or moving the canister filter closer to the system... or both. Bob Fenner> Thank you Jamie

Re: Extra filter pump for Fluval 404 Thanks Bob for the suggestions, I would say I have about 12 - 15 feet of hosing round trip drop & rise for hoses would be about 3 ½ to 4 feet). <Good input, once again the height is of little consequence... as the water is "pushed" as much as it is "pulled" with the lines originating and ending at the same approximate level (relative to the mass of this planet.> The intake side, is the Fluval intake pipe that comes from manufact. The hose travels down the back side of the tank to a bulkhead in the wall. I live in a Bi-level house with a crawl space under the steps. Fluval & UV are placed here for easy access.  <Oh! The induced drag through the sterilizer may be significant... could be a/the deciding factor... possibly might be worth experimenting here... cutting the hose between the canister and U.V. and inserting the Mag 7 there...> The return side is configured in a similar manner with another bulk head in the wall returning to the tank the cleaned water. The new hoses are ¾ , <Is this 3/4"? I hope so. Can't make out the tiny print> I think the Fluval hoses are only ½, which I don't use anymore. I thought maybe the Mag 7 after the UV to help draw the water back up to the tank. <Not made to "draw" but to push... hard on the pump... may cavitate badly if placed to "suck"... Bob Fenner> Thanks Jamie

Marine set-up query Hi Anthony <cheers> Sorry, one last thing. I checked my 2ft tank for fit in my 4ft cabinet last night and had bit of a thought upon seeing the sump and Fluval 404 together. Could I run the 404 intake hose from the sump and use it to pump the sump water back up to the tank ? <no my friend. This great little filter was not designed to handle that sort of head pressure. You will need a dedicated pump for the purpose> Cheers, Scott
<kindly, Anthony>

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