Sadly, today I was not able to buy a new filter for my fish as I had planned. I need to wait until I have more available funds I was going to buy a Penguin 350 for my 20 gallon tank, which is very overstocked with four large commons. They should be getting a new 55 gallon home within 6 weeks.

Since I will have to wait about two weeks to get the new filter, I decided to add a second filter that I already have. I am wondering where I should put it to make the least amount of current for the fish, and to get the best filtration.

They are both Whisper in-tank filters, which unfortunately, take up a lot of space in the tank, but they will have to do for now. One is a 20i and one is a 40i, so together they do 295 gph for my 20 gallon tank.

The fish were seeming kind of stressed, two of them have red veins in their tails. I added some salt to the tank last night to see if that would help, but I know water quality is the key, so I thought I should use the second filter until I can get the Penguin.

On a bright note, I had my first ever 0 ammonia reading today, since I have had the fish, which has been about 2 1/2 weeks.

So right now I have the filters facing each other, one one end of the tank. One on the back and one on the front. I was thinking that will leave the other side of the tank without current, but I am hoping it will still filter well.

Thanks for any advice, or let me know if this placement is ok.

Hi,

Sorry about your hitch in getting a new filter. Still, you've done the right thing to install the spare filter.

Overfiltration is preferable to underfiltration, and in your case, I think turbulence will be key in filter placement.

The gph of your filters do not appear to be that overpowered for your tank, so I'd stick with your current arrangement, provided your fish aren't stressed. If you notice that your fish need to be constantly swimming against the flow, perhaps you could baffle the outflow with plants/ornaments, or direct the outflow to the tank wall first.

Hopefully, with your additional filter, your water quality and fish will perk up

Slugger

Thanks! Today they seem a little better already, although that could be from the salt also.

I think they are ok with the current, they can go over to theother side of the tank or under the filters and have seem to have no trouble staying still without swimming.

I got my first 0 ammonia reading yesterday as well, which is encouraging, although last night I had nitrites in my tank for the forst time since I have had the fish, .25 was the reading. So I am keeping a close eye on that.

Thanks again for your advice! Dueling filters reminded me of the song dueling banjos, hence the subject title. I will be able to get the new filter within two weeks, and it will not be the in tank kind, so it will free up more space for the fish, and hopefully not create too strong of a current. And then soon after they will get to move into a 55 gallon! Yay!