Hi I was wanting to have my future tank drilled so I could plumb in a sump. I went to a local petstore (was bored witing for my connecting bus back fro college) and I found the exact Tank and stand I was getting. Luckily I had my ruler with me and found out the stand could only fir a 12"x10" tank

So I thought the hassle of drilling a tank ect. would be justified by such a small sump. I would only have room for the inlet pipe, heater, outlet pump and some cheato. So I went searching and found this HOB refugium on eBay.

I live in the UK so its the UK site.
HOB refugium

To me looks pretty good solution. I am thinking I should remove the bioballs. Also what is this "miracle mud" stuff like, any good or should I use something else. I plan to grow some macro algae as well, along with the Live rock in my tank do you guys think this will be suitable filtration for a 30 Gallon tank housing around 4-6 fish?

I wouldn't waste my time with the bioballs or that "miracle mud" stuff. Elsewise it looks like a nice set up for a HOB refugium from that link.

The added water volume, the macro algea will help your tank as long as you don't have debris build up that will create a nitrate factory. Your primary filtration is the live rock providing the biological filtration. Chemical filtration is when you add carbon and/or gfo, etc., and mechanical filtration is using filter floss or the like. Your macro algea growth is nutrient export when you harvest it.