I'm in the later stages of the nitrogen cycle. My nitrites are about 2ppm and nitrates are about 4 or 5ppm. Due to the rarity of 40 gallon breeder stands I decided to try a metal racking from home depot. It holds 1,000lbs and fits 2-40 gallon breeders one on top of the other. I estimate a total of about 700lbs including sump, rocks and sand. This setup is in a sitting room in my home and will house my current livestock until I finish my basement man cave. I'm building an in the wall setup. I'm thinking a 200g predator tank with some type of flashy looking eel as the centerpiece. I'm using a diy pvc overflow with a toms aqualifter to automatically start a siphon in case of a power outage. I took a 2inch black pvc pipe, cut it to size and with a dremel I notched teeth into it. I siliconed it to the bottom of the tank. It acts as a weir, the water spills over into it then my 3/4inch pvc overflow drains it into the sump. I ordered some glass to be cut so I could silicone baffles into the 40g breeder sump. The sump is very basic, it has 3 chambers and a bubble trap just before the return chamber. The first section of the sump is the largest section and will be filled with chaeto, I'm not sure what I will keep in the second chamber. I have a skimmer but I'm hoping the chaeto grows large enough and removes enough nutrients so I won't have to run it. Maybe I'll add more chaeto if I see that it's working well.