I am saving money on filter media, because i use un-needed test tubes and caps as biological media, it works great if un-needed and clean, same with broken off pieces from a plastic plant, coke bottle tops, caps from food canisters and i use like empty dechlor bottles to take a little water out of my betta tank when i redecorate it as to not displace the water than replace it when i am done. Everything is resuable
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