# What gph for 90 gal tank?



## Vlad

I just got a 90 gallon aquarium and I need to know how many gallons per hour filter i would need.


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## Betta man

I think you'd need about 110 gallons per hour. That should do well as you want to get overkill not underkill.


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## Superfly724

I use a Fluval 305 and 2 Penguin sponge filter/power heads. The Penguin filters both push about 170 GPH, and the Fluval pushes about 260 GPH. Maybe it's overkill, but it works. The Fluval 305 box says it's for up to 70 gallons, so I didn't want to take chances.


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## lohachata

the standard for filtration turnover rate is 10x.....that means 10 times the tank volume every hour...in your case that equates to 900 GPH.....in my 125 i run 6 large sponge filtrers and a Fluval FX-5....
hmmmmm....110 GPH is just over 1 time per hour...way under filtered...


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## Vlad

Wow, 3 very diffident answers lol


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## Vlad

I was going to take a mag/pump like this and put it in a 2 gallon bucket to make a filter. would that work? 


http://www.pondworld.com/pm-mag-950.aspx


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## Fishpunk

It depends a lot on what you plan to keep in the tank and how sensitive to current. lohachata's 900 gallons per hour is a quarter gallon every second. That's a LOT of current to put into a tank That's like emptying a gallon milk container into the tank in 4 seconds, and I guarantee you can't dump it out the top of the container that fast. 

Many fish can't handle that kind of current.


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## phlyergirl

Fishpunk said:


> It depends a lot on what you plan to keep in the tank and how sensitive to current. lohachata's 900 gallons per hour is a quarter gallon every second. That's a LOT of current to put into a tank That's like emptying a gallon milk container into the tank in 4 seconds, and I guarantee you can't dump it out the top of the container that fast.
> 
> Many fish can't handle that kind of current.


I agree. Depends on what you'll have in there, not just with current but bioload too. Filling a 90g with neon tetras would need a lot less filtration than putting oscars in there, for instance.


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## Vlad

Honestly I don't know yet. I should of thought this through before making this post., thanks guys


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## emc7

SF uses 3 filters for 600 gph. Not bad considering how lightly its stocked. For mbuna, you'd want the 900. For a few neons and a boatload of plants, not so much. But 1x per hour? That's pretty puny. Are you trying to protect bubble nests or Co2?


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## funlad3

Fishpunk said:


> It depends a lot on what you plan to keep in the tank and how sensitive to current. lohachata's 900 gallons per hour is a quarter gallon every second. That's a LOT of current to put into a tank That's like emptying a gallon milk container into the tank in 4 seconds, and I guarantee you can't dump it out the top of the container that fast.
> 
> Many fish can't handle that kind of current.



It sounds like a lot, but in actuality, it's not. I have over 2000 GPH on my 90 gallon reef, and it's not enough to even make my sand think about moving. 1/4 of a gallon per second is spread throughout the entire tank. 

Right now at 900GPH, you'd be moving 32 ounces of water per second. In a 5"x6" area, that's barely more than a single fluid ounce of water per second. Really, your only moving .0015 ounces of water through a cubic inch of tank per second. AKA, not a whole lot.


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## emc7

A fish club bud made a 5 gallon bucket into a filter for a large tank. It eventually did the job, but he had to stop and fix leaks 3 or 4 times. Most people use the largest tank that will fit under as a sump. The larger the filter, the less flow you need.


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## Maine_Fish

In my tanks, I typically aim for a turnover flow rate of 8-10X per hour. There are, of course, scenarios where this kind of water movement might not be desirable.


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## mike88

In my experience and opinion 4x an hour is minimum. 90 Gal = 360 gph filter would be the absolute minimum i would use.


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## lohachata

i have a 90 gallon tank that i will be putting a FX5 on along with a few big sponge filters....
900 gph sounds like a lot of current but in my case there is very little...the end pieces from the intake and output of the filter got broken during a move...so i modified it...on the intake i attached an 18" piece of pvc pipe with holes drilled all over it and then put a cap on it..on the output i made a 36" spraybar from pvc.....5/16" hole every 1 1/2"....the current is very gentle...


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## Vlad

What do you think?

http://www.ebay.com/itm/Emperor-400...t=LH_DefaultDomain_0&hash=item1e6c1af429#shId


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## lohachata

see where it says "for up to 90 gallons"...that means you need 4 of them...


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