I've done a little work on the unseen parts of the tank. I made some lids for the sump and tank out of poly carbonate sheeting that I found in the roofing section of the hardware store. I also butchered a container to house the mechanical filter and plumbed in the continual water exchange hoses.
The ugly black sticks are air diffusers that I made for the MBBR. They are 4mm irrigation sprayer risers, drilled every 5 cm or so. The blobs are aqua knead it (putty), to give it some weight and hold them in place.
The blue air pump fuels the MBBR. It's a great pump for the price and very quiet, considering that it pumps about 30L/min.
The little white air pump appears to be a great bit of kit, time will tell. This thing has an internal battery, in the event of a power failure, it will continue to run for approx 40hr. I'm going to try and hide the outlet of this somewhere inside the tank. I hate air bubbles in aquariums (Its a personal thing) But I hate fish losses due to power outs even more, so I'm very happy to have this on board. Its the cheapest, easiest back up system that I could find.
I still have no return pump It's coming on Monday, apparently. I got a jebao DC 12000 on its way. Massive overkill but variable speed and useful if you need to stir things up. The last one I had lasted for a good few years.
Still waiting, impatiently, for my wood to sink so I can do more decorating.