Ghostridergt,

There's no more updates to that system. It was my first system and I moved out of that apartment shortly after those last pictures were taken. I will see if i can dig up some pictures of my second system so you can see the progression of my learning and my aquaponics "style". The second system is in the back yard of a rent house so it was considerably bigger. I am also about to start a new thread of my current (third) system which is in a more permanent place since i bought a house. The system have progressively gotten bigger.

To answer your question i think i ended up with about 22-24 tilapia in that 100 gallon tank... That is definitely not the maximum load but it's a comfortable load for me.

Things i would change if i was rebuilding that system.
1) i would not put sand in the tank.. I thought it was necessary because i wanted to get the tilapia to reproduce... a substrate at the bottom of the tank is not necessary> Alls the sand did was absorb stinky waste and was an epic pain to move.
2) I try to design all of my systems using only 1 pump. It was difficult in that situation to use one pump because of the layout and space constraints but I am sure if i had thought it out better i could have limited to using 1 pump instead of 2 or 3.
3) I dont use hydroton anymore... it's just too expensive and there's not enough benefits to justify the money. I mostly use expanded shale now. Which is pea sized. I still use the hydroton that i already own in areas where the fish solids enter the grow bed. The larger hydroton lets the solids sink into the bed easier.
4) i wouldnt put a system of this size indoors in a house or apartment because the plants just give off too much humidity and damage the interior of the house.
5) in that system i used timers to turn my pumps on and off. I now subscribe to the line of thought that starting and stopping your pumps causes a disproportionate amount of wear and tear and i now try to design my systems where i can leave the pump on 24/7.
6) i prefer pumping from a sump to the fish tank and overflowing the fish tank into the grow beds. grow beds drain to sump. I believe people call it CHOPS.