An interesting development on the filter-front. James had decided that the sponges on one side of the Fluval (the other side has holders for carbon and bio stuff) were pretty much useless, mostly because food and other particulates were getting into the bio bit, which we figured probably wasn’t such a great thing. So we turfed the sponges and replaced them with filter wool – just stuffed it in, but didn’t pack it down. Also put a layer of it in each of the holders, over the bio stuff and the carbon. And when we checked this morning (hoping that the filter was not totally stuffed): hooray! The top of the wool was almost black and had caught almost all of the gunk! The great thing with the wool is you can just pull out the grotty bits and replace it. There was nothing in the bio bit – no food; James says other times, there would be food and stuff floating around in the filter canister when he opened it up – not this time! Later edit: this may also have been because of over-feeding…