# GPH to Aquarium Size



## GeToChKn (Apr 15, 2011)

I always like having several filters if possible on a tank. Makes cleaning easy as you can clean one really good and alternate the cleanings by 2 weeks or a month. Also, if one goes down, you're not stuck there waiting to get a new one with no filtration. On a tank 125gal, circulation can be a problem and you can position 2 of them at either end with intakes and outtakes and get a good flow going. My 125g has a 25gal sump on it, and now having that, I would never get a big tank again without a sump or mess around with canister on a tank that size.

As for the GPH, some list it as pure GPH at the shortest distance with no media in the canister to get a nice high number. Others give more realistic numbers with it run full of media at the max tube run length, etc, so it depends on how honest they are being.


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## NWA-Planted (Aug 27, 2011)

I may have to look into a sump, any good links for DIY?


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## GeToChKn (Apr 15, 2011)

I'm sure there is a million pages out there about it, mostly on saltwater sites. I bought my tank already drilled, overflows built in, sump, stand, whole deal so I don't know much about making it other than if I was, I would copy my design exactly. lol.


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## NWA-Planted (Aug 27, 2011)

*ponder* lol


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## SlammedDC2 (Jun 4, 2011)

check out www.monsterfishkeepers.com they have alot of good write ups on DIY sumps.
I recently set up a 29g sump on my 125g and love it. I have a HOB overflow rated at 1200gph and a return pump capable of 1350gph.
Crystal clear water, constant water level, and all the equipment is hidden in the sump.


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## Sharkfood (May 2, 2010)

There's something of a "feel" to sizing filtration for your tank. Most manufacturers grossly overrate the GPH you will see from your filter. Eheims are a little closer to being true, but still rated higher than you will see in practice.

In most tanks, I would shoot for 8-10X the size of your tank (EX... 100gph for a 10 gallon tank.). If you go by tank size recommendations from the manufacturer (I.E. "Rated for a 55 gallon tank") cut the number by 1/2 to 1/3. There are different types of tanks and you may want to ammend this advice for your particular setup.

You don't want a river tank for your betta, and a school of dace don't appreciate pond-like environments, so you have to exercise a little judgement. Another consideration is how plant mass and scape will reduce flow. 10-15X flow rate may seem like a lot in an empty tank, but heavy vegetation will seriously reduce water movement. Then there is outlet placement, diffuse versus concentrated current etc. Generally, the 10X rule has always served me well in the past however.


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## Mxx (Dec 29, 2010)

I tend to see recommendations of 5-10 times turnover of the tank's volume per hour, and many do more or less with fine results, including 0 turnover even for some filterless low tech planted tanks. With quite a wide range of recommended flow clearly flow isn't necessarily that critical a factor. 
There are however many different factor to consider here, every tank will have different things affecting flow patterns, different fauna bioloads, different flora amounts which also can help maintain water quality, different light levels affecting the effectiveness of plant metabolism, etc. 
The actual effectiveness of different filters mechanical filtration, and how long that will last before becoming ineffective and requiring cleaning is a different matter as well. 
And perhaps filter media volume is more important than flow, if a given tank requires bio-filtration and if the plants aren't doing the entire job. 
So how is that for a completely indeterminate answer to your query?


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## NWA-Planted (Aug 27, 2011)

roud:


Mxx said:


> I tend to see recommendations of 5-10 times turnover of the tank's volume per hour, and many do more or less with fine results, including 0 turnover even for some filterless low tech planted tanks. With quite a wide range of recommended flow clearly flow isn't necessarily that critical a factor.
> There are however many different factor to consider here, every tank will have different things affecting flow patterns, different fauna bioloads, different flora amounts which also can help maintain water quality, different light levels affecting the effectiveness of plant metabolism, etc.
> The actual effectiveness of different filters mechanical filtration, and how long that will last before becoming ineffective and requiring cleaning is a different matter as well.
> And perhaps filter media volume is more important than flow, if a given tank requires bio-filtration and if the plants aren't doing the entire job.
> So how is that for a completely indeterminate answer to your query?


roud:

lol


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## Daximus (Oct 19, 2011)

NWA, I assume this is in reference to "our" Aquatop CF-500UVs? I know this isn't the thread for reviewing canisters, but I was wondering what media you ended up putting in yours? 

For those that aren't familiar with this pump it's rated at 525 gph, loaded I'm guesstimating 300gph. One thing about them, they come woefully unloaded with media in my opinion. I absolutely love mine, flow is perfect for my 90g tank (Angels, Discus). 

Anyways, if you have the means and the space a sump is the way to go in my opinion. You can hide everything, play with the water chemistry, add Co2..etc all without disturbing the critters. That said, I've seen sumps that looked like they had about 4 lbs of ceramic tubes and God knows what else for media.

My point being, if you haven't added a significant amount of media to that huge can and let it cycle for a while you may not be giving it a fair shot to operate at it's peak. :icon_mrgr


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