# fluval U series underwater filter



## nhra_20 (Mar 22, 2010)

Hey there. Has anyone used the fluval in-tank filter? I saw one at my LFS and thought about getting one. It says they have all 3 steps of filtration in them, but what caught my eye is the out put on them. Looks I could use it to add air as well as circulation. It is the fluval U series.


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## aaronjunited (Sep 29, 2009)

I have the Fluval U2 in my tank with oscars and bala's and a sajica. Its the only filtration i have in the tank.

Its a nice filter, the white sponge and black sponge sit tight together and you put them in casing which slides inside the filter, one on each side, then you have the biomax balls which fit in there own case and slide inside the filter in the middle. Venturi valve on top must sit slightly out of the water for air to come in.

They definately clean the water well, i always have crystal clear water with just that filter running. The flowrate is brilliant, plenty of water movement and surface movement and loads of oxygen going into the water.

Easy to clean also. Just take filter out put in bucket of tank water *** just taken out and rub them in the water, back in there casing after cleaning the inside of the filter and in they go, close the lid and your done. Put the filter back on its holder in the tank and switch her on. (this gathers dirt too, best to clean it sometimes aswell)

Replacement media isnt dear and neither are replacement parts.

I also have the fluval U3 which is the one up from the U2 and its going into my new mbuna set-up along with a canister. Its bigger in size and better flow rate obvisouly.

Great filter is you ask me, havent replaced any parts yet, i clean every two weeks and thats all the tank needs.


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## nhra_20 (Mar 22, 2010)

alright. I don't need the extra filtration really, since I have a rena XP4 on my 54 gallon tank, but if it can add air, move water AND filter water sounds like a good deal. And my LFS has them on sale for 1/2 off which puts them at same price as any other piece of equiptment that would just move my water areound and add air


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## aaronjunited (Sep 29, 2009)

For whatever reason you buy its definately a brilliant filter. Just make sure you match with your tank. U2, U3 OR U4.

Brilliant filters.


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## aaronjunited (Sep 29, 2009)

If you dont need the extra filtration you will definately get water movement and plenty more oxygen going into your tank. And the over filtration will keep that water in pristine condition. You'l see a big difference.


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## cjacob316 (Dec 4, 2008)

add air? just because it has an airline attachment does mean it's good for adding air, it just means it creates bubbles, the key to oxygenating your tank is water movement and water to air contact, and most contact your water will have with air is at the surface, so moving the surface is what you need if you want air bubbles buy a $.10 air stone


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## aquariam (Feb 11, 2010)

cjacob316 said:


> add air? just because it has an airline attachment does mean it's good for adding air, it just means it creates bubbles, the key to oxygenating your tank is water movement and water to air contact, and most contact your water will have with air is at the surface, so moving the surface is what you need if you want air bubbles buy a $.10 air stone


I agree venturis create ugly giant inefficient bubbles which are less practical than the diffusion created by an airstone.
The primary benefit in my opinion of running an airstone in FW is that it breaks up the surface slick (that rainbow colored stuff) that can accumulate, blowing it back into the water where it can be processed by your biofilter.

The actual air bubbles themselves increase oxygen levels by no more than 10% I have read many times. What creates extra oxygen, as mentioned, is the water moving at the surface, and in that regard, the fact that the bubbles push water across the surface does in itself add more oxygen that the air pumping through the water (also, just what I've read).


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## aaronjunited (Sep 29, 2009)

but the ugly giant bubbles is oxygen the more bubbles the more oxygen and the more water movement also. the flow rate of the water coming in to the tank is amazing it moves the surface and creates current which are all good things no matter how many filters you have on your tank.


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## cjacob316 (Dec 4, 2008)

i think you're missing the point.

yes if you stick the filter near the surface so that the jet disturbs the surface it is helping to oxygenate the water much more than if you attached an air line and pushed the filter toward the bottom on the tank and relied on he bubbles for an oxygen source

since these fish are from a lake, they may not necessarily like a strong current whipping the water around the tank, so loading your tank with tons of filters for current isn't always the best or most efficient thing. bigger and more isn't always better

an xp4 is already almost considered overkill for a 58 gallon and as long as you have pretty good turn over and surface agitation, as well as no oily film gathering on the surface you're fine, and adding an internal filter that basically just takes up a chunk of space inside the tank wouldn't do much to help, you're better off with an hob and it doesn't crowd your tank as much


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## nhra_20 (Mar 22, 2010)

Me personally I have never heard of over kill on a filter system. Don't think anyone will ever say "wow your water really looks too clear" I bought the XP4 with expectations of the amount of waste african cichlids produce and also having it well stocked. I have a crapload of biological media in there and a little carbon. Took out the polishing pad though. My water stays pristine I do about a 15% water change and gravel vac every week. And once a month I do about a 50% water change.


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## cjacob316 (Dec 4, 2008)

if your water is pristine then you don't need another filter


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## nhra_20 (Mar 22, 2010)

I was just asking about one more for the water circulation purposes. I like the fact that it has three different outputs to choose from.


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## aaronjunited (Sep 29, 2009)

the water circulation will be greatly increased while using one of the Fluval U filters, trust me.


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## bertolli (Aug 18, 2009)

lol aaron u sure u dont work for fluval? :lol:


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## aaronjunited (Sep 29, 2009)

nope definately not lol, i'm a bum, i dont have a job.


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## MCKP (Aug 17, 2009)

We use a U4 also and I really like it alot. The fish love to hang in the current and it does a great job keeping my tank clean. I also like I don't have to worry about it leaking! hehe and it is silent! I am looking for a canister because they don't have a large enough underwater filter for my 125 and I just don't like the look of 3 of them in the tank! LOL But for my smaller tanks, I am very happy with it! We are getting a U2 or U3 for my 20 too...


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