Hi guys I've posted on here a couple of times and am new to this saltwater hobby. Never having a fish tank before this year I decided to go with saltwater...and boy did I not know what I was getting into!!! After a month or two of mostly downs I learned the ropes the hard and expensive way. Now finally my tank has been establish for around 2 months with its inhabitants being 2 ocellaris clowns, 1 fire fish, 2 blue legged hermits, a bunch of snails and a Red Bali star fish. I have now about 10 lbs of live rock and 40lbs of sand in my 14g biocube. Fist off any suggestino of additions to my tank (coral, invertebrates, corals, fish) as xmas is coming up and I need to ask for gifts!! Anyways so I have seen a lot of threads on this forum and others about modifying a biocube or other nano to not only make it a better environment for your inhabitants but easier on the wallet (which excited me)!! I use to have a $40 dollar in-tank refuguim with about 2 inchs of live sand, a handful of chaeto, and 2 lbs of live lava rock which I then found out that lava LR contains heavy metals and invertebrates don't do well with it, so i quickly discarded of the lava and bought 3 lbs of base rock from a LFS and chiseled it into rubble. After having my intank setup I found out how I can mod the back of my biocube into a refugium (and also that my nitrates were high which were caused my bioballs and sponge filter having old detritus stuck in them). I also saw that I would be spending 10 dollars on biocube filters every 2 months at the most sometimes even more so thats $120/year on filters. Thats a lot of money so i also found out on these forms about purigen and blue bonded filter pads. Purigen cost $6.99 last for 6 months and through bleaching can be reused and reused over and over. Also blue bonded filter pads can be bough in bulk, for $6.99 at my LFS and last twice as long as the biocube for the same size so on $6.99 purchase will last me up to 2 years. Thats a saving of $226 over the first two years. (thats a couple corals!!!) Here is my thread for all the newbies that think these mods are to confusing, I'll help you through them with step by step and pictures.