I have an enternal filter it came with the tank. its 7.5w and 550l/h. And I have a wand which is 40 cm connected to 2 pipes from each side. And the 2 pipes r connected to a machine outside the tank. The filter that I have circulates the water from the bottom and then dump them inside again. 10x
Well, if you already have a filter, you do not need another filter. You can get another filter only if you want to. But if your tank will be overstocked (too many or too large fish), it would be good to have two filters.
Does the filter you have lay under the gravel and have tubes that come up on the sides of the tank with airstones? That is called an Undergravel Filter and if you are going to have Tropical Fish it is not the best type of filter to use, but I do not know what to tell you about the other filter until I know if this is the type of filter you have.
[The filter that I have rose is internal filter its not an undergravel filter. Its inside the aquarium and there is a plastic thing in the bottom above the gravel it round. It take the water from the bottom of the tank and circulate it and then dump it. I want to know if it is enough for the tank or I should get another filter. !0x