Internal water filter

[Pariis11]

Hello can anyone recommend a good internal Walter filter for a 120litre tank.

Will also take suggestion on an external one but not too big as I’m stuck for space

 

[KarenSoCal]

If you mean filters like what we use with an aquarium, first you need to decide what kind of filter you want.

For inside the tank, I use small submersible internal filters like these....this one isn't mine, but it's the same design.
https://www.amazon.com/dp/B07S9PQM92/?tag=exoticpetnetw-20

For just a bit of filtering, you can use a sponge filter, but I doubt it would suffice for turtles.
https://www.amazon.com/dp/B071HVZVMP/?tag=exoticpetnetw-20

For outside filters, there's mainly 2 kinds. A HOB (hang on back) filter, and a canister filter. Hang on filters look like this...
https://www.amazon.com/dp/B000260FUM/?tag=exoticpetnetw-20

They are very popular, easy to use, and come different sizes for various tank capacities.

Canister filters are the real workhorses when you need heavy duty filtering. Like this....
https://www.amazon.com/dp/B0002DJ9NY/?tag=exoticpetnetw-20

They sit on the floor beneath the aquarium.

A little tip...when you need to buy a premade filter, or filter material, use this instead.
https://www.amazon.com/dp/B004ALQ0M2/?tag=exoticpetnetw-20

It's polyfill for stuffing pillows, quilting, stuffed animals,etc. Here a big bag costs $4. It's the same stuff they sell as filter material, for a lot less money. I buy it at Walmart.