I just put a peice of PVC pipe in my tank and buried it with sand a placed some LR over the top of it to hide it. The eel really likes his new home (although it was intended for the engineer goby). I was thinking about getting some more pipe and some elbow joints and making him a kindof luxury home. The question is do i need to find a way to circulate the water through the pipe or will the eel swimming around in it do enough. I dont want the water to become anaerobic and possibly kill my eel. Thanks