From what I was reading and looking into. A co2 scrubber is not exspensive in comparison to anything in this hobby. It can be made out of a two litre soda bottle. Media is not so bad either if bought in bulk. real concern would be if it works for u or not. Dosing is exspensive , unless u make your own calk / alk / mag. I am going to be trying one on my new system see if ph holds up. If not I'll switch to dosing.