Update 5 (Lots of changes!)
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Filtration
New filter, the buzzing from the Fluval 306 was driving me mad so I replaced it with the Hydor Professional 250 and I must say that I'm very impressed. The telescopic intake and modular spray bar make the pipework extremely versatile and the construction of the canister seems much better than the Fluval, with minimal chance of water bypass.
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Lighting
The 38W T8 light was well past its prime and it was beginning to show in the plants. So I took the whole thing out and made a DIY CFL light fixture out of some gutter and aluminium tape. I've now got 100W of lights, still directed at the rear of the tank, which should allow for the growth of higher light plants. The other advantage of CFLs is that when they stop producing photo-synthetically useful light, I can just swap them out for new ones and carry on using the old ones in ordinary house light fixtures. I have it set so that one light comes on at 8:30am, with the other four joining it at 9:00am. The latter four then turn off at 6:00pm, with a single light staying on until 6:30pm. This creates a more gentle transition so that the axolotls aren't too shocked when the lights come on. At night I an RGB LED strip which I have set to a dim white until I go to sleep, at which point I switch it to a dim blue to mimic moonlight.
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Bogwood
Found an excellent supplier of bogwood that was able to ship me some beautiful pieces for a very reasonable price. I let these soak for a week in the bath, just to make sure that all traces of tannic acid had been removed. I've since added them all to the tank to continue soaking as two of the pieces still float, and two others are not completely waterlogged. I absolutely love the new look! Not only does it provide complete shade from the lights, allowing me to do away with hides that obscured my gorgeous axolotls from view. But also creates a very natural, swamp-like, feel in the tank. The axolotls seem to really enjoy the bogwood. They've been much more active that usual, clambering along the new levels to the tank!
Fish
After much deliberation, I took the plunge and purchased 10 cloud mountain minnows, 10 female guppies, and 4 male guppies. I quarantined them for a fortnight, but since I knew the previous owner, I could be confident that they were healthy and added them to the main tank. I was scared initially, as 2 of the minnows started nibbling at the gills of my albino. I waved them away and haven't seen any violence since. I lost 2 guppies due to jumping out, and 2 more have disappeared, but 20 fish still remain and give the axolotls a wide birth. The axolotls ignore the fish for the most part, occasionally stalking them but never fast enough to catch them! I'm glad I chose to do this, it really spices up the tank, adding movement to the upper levels and really filling out the aqaurium. All the female guppies are pregnant but I am not sure if they will give birth at the low temperature of the tank.
Happy axolotls!
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