With Power Filters, How Many Gph Does A Tank Need?

[wendywc]

I have a 55 gallon that I need to get a power filter for... actually I was thinking of getting two power filters. All power filters are labeled with how much GPH they handle, but not what minimum tank sizes (in US gallons) they are for. How do you convert this?

For the 55 gallon, I was looking at getting two 200 GPH power filters. Is this enough? Too much?

Also, out of curiousity, I have a 250 GPH power filter on my 30 gallon tank and a 75 GPH power filter on the 6 gallon tank. Am I overfiltering? If so, ny how much?

 

[dthoffsett]

Ideally you want the filter to turn over the tank water 5 - 7 times per hour. So, for the 55gal you want a total of 275 to 385gph. On the 30 gal 150 to 210 gph, and the 6gal 30 to 42gph.

 

[wendywc]

Thank you!

What do you think about having two (2) 200 GPH power filters for the 55 gallon instead of one (1) 350+ GPH filter?

 

[kramers]

I'm no expert on the subject, but at he moment I'm running 2 Biowheel 350's on my 55g with 2 filter carts in each. So far I haven't had any probs with it yet, if this helps.

 

[steelhealr]

Wendywc....we 'salty' folks on the lower half of the page are dependent on powerheads for circulation in our marine tanks. I think the setup depends on what you want to create. If you use a single PH you are going to have a high output area with strong current near the PH with decreasing flow secondary to resistance further away. If you use 2 PH's, you can either maintain more of a strong current throughout, or, cause turbulence or dead spots depending on how you aim them. It just depends on what type of scenario you want to create in your tank. SH

 

[wendywc]

Ahhh. That supports what I was thinking. I'll probably get two then since the tank is 4 foot long; one powerhead on one end and one powerhead on the other end.

 

[steelhealr]

Sounds fine. SH

 

[guppymonkey]

I try to filter my tanks 10x each hour, at least with the larger fish. In my oscar tank I filter the tank with a combination of three filters (I would have to check the filters to find out the gph) and it gets circulated about 14 times an hour. Some people would say thats too much filtration but the oscar loves it. He has a good area with a current he can play with and then an area of lesser current. With smaller fish though it might be a little overdone, they wouldn't need the filtration as high because they produce much less waste (and destruction) than an oscar.