After some searching, I 'think' I found your brand tank and here is the instructions for how to set it up https://www.tropicalfishstore.com/System-2-Instructions-2002.pdf
If you don't already have the bioballs, you could always choose another type of bio-media to use in mesh filter bags.
Can you post a pic of the entire top of the tank? Usually access to the filter media is a bit of a pain on these type of tanks since the openings are so small.
If you don't already have the bioballs, you could always choose another type of bio-media to use in mesh filter bags.
Can you post a pic of the entire top of the tank? Usually access to the filter media is a bit of a pain on these type of tanks since the openings are so small.