Appropriate GPH for different tanks?

[Lars]

I have a 40 gallon currently. I am using a Tetra EX45. It's not a terrible filter, but you cannot adjust the filter rate with it, which is lame. I was considering getting a Fluvial HOB, as you can adjust the flow rate. I think my siblings are different genders, so I was going to get a 20 long for it, and a Fluval as well.

My question is: what would be an appropriate flow rate? What's the recommended GPH? I don't just want to turn it on the lowest setting and hope for the best. I'd still like for the lotls to receive appropriate filtration. Thank you!

 

[keiko]

I think about 4 times the tank volume per hour is the recommendation. The current can get pretty strong, but you can get a spraybar that'll help a bit.

 

[sde]

You can diffuse the amount of current it puts into you're tank by.....

A) Putting a sponge in/in front of the output of the filter.

B) Putting plants where the water is being pumped back into the tank.

C) Putting plastic rap with holes in it in from of the output.

D) Using a spray bar and having it spray into the side of the tank ( water might splash a lot though ).

Hope this helps! -Seth

 

[mewsha]

as Seth said the spray bar is really good! i got a cheap filter which came with one and the current was pushing the fish flakes (currently cycling the tank) everywhere, so having it facing the tank side definitely helps. to stop splashing i had the spray bar under the water a bit

 

[Xtophr]

The Tetra EX45 is a HOB; here is a pic for one option to disperse the water:

Axolotls - Housing in Captivity

 

[sde]

The first three dispersing methods I listed are still applicable to a HOB. In fact, the first and third ones probably work better with HOBs.