guppy tank smells bad right after tank cleaning

[finfayce]

i originally wanted a few young guppies for my red eared slider. the vet said the turtle would benefit from live food. the neighbor gave me some (fancy) guppies- male and female. the turtle won’t eat guppies and i have too many guppies. i have downsized by giving guppies to Petco. my question is how many guppies should be in a 20 gallon tank? i just bought a new Cascade 600 internal filter, which is supposed to clean a 50 gallon tank. also i have the small Tetra Whisper 10i despite the filters and regular water changes, the tank smells bad after 2 days after filter cleaning and water change. i have used API. accuclear and Fluval biological cleaners. what can i do to keep the tank from smelling bad?

 

[Back in the fold]

If you have a turtle in there that's where the smell is coming from. Turtles are dirty.

 

[FishGuest5123]

Are you vacuuming the substrate really well during cleanings? That’s where all the gunk falls. You can add charcoal to absorb odors.

 

[FishGuest5123]

If you have a turtle in there that's where the smell is coming from. Turtles are dirty.

Oh gosh, I agree! Forgot about the turtle. I use to sit down in my den and could smell my turtle tank from across the room when dirty. Good way to get me to clean the tank though.

 

[Colin_T]

Do a 75% water change and gravel clean the substrate every day for a couple of weeks. Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. Wash filter media in a bucket of tank water.

Increase aeration/ surface turbulence.

Remove covers form the tank.

Open doors and windows to let the room air out.