I designed this cradle so I can build my own fish tank filters. The Marineland Penguin 350 (Requires 2) filters and that they be replaced every 2 weeks. A box of these filters is $25 and come with 6 filters total. The cost to end of life is $25 every 1.5 months, which can be costly.
I bought 2 socks ($6/Ea), Filter Media Pads ($10), Carbon Media ($15), and Nitrate Media ($15). The Carbon and Nitrate media is said to last a month and the Filter Media is every 2 weeks. Based on my experience with this setup, I am about $30-$40 every 4-6 months
OEM Replacement Filters - $25/1.5 Months = $16.66/Month
DIY Filters - $35/5 Month = $7/Month
I was able to leave the tank uncleaned/no water exchanges for 1-2 weeks without any incidents. I felt the tank keep itself overall cleaner then using the OEM filter replacements.
I was able to print these with no supports needed.
Note: One item not in the picture, I have a generic half inch sponge filter material on the bottom that this cradle rests on. This sponge helps collect sedimate that might fall to the bottom as well as give it the desired high for optimal filtration.