A very nice build indeed. The cyano is killer to get rid of. when it forms on the sand try to scoop it out gently as a whole. or suck it out with a syphon. try not to stir it as that will sometimes keep it in the system. do you have any sand sifting stars? they are great from keeping the detrius off the bottom which i think is what the bacterium feed on. there is also a site
Geothermal Aquaculture Research Foundation Home Page I highly recomend you getting a pound (or 10 in your large tank case) of their GARF grunge to put over the bottom of your tank. That will help kick in your sands ability to help you get rid of that bacteria. Just my 2 cents. Nice tank and stand by the way. You have some nice carpentry skills (I acn't spell)
Oh yeah, any more pix?