If you are feeding minced meat make sure it does not contain sulphur dioxide. I fed some to a baby magpie once and it spewed like a volcano. The butchers are not supposed to add it to minced meat but some have been known to (if they add mutton it goes grey and the SO2 makes it pink again)
It is all about balance. Fish can survive quite well in an aquariumm without aeration or a filter provided the tank is not overloaded with fish. What we do often is raise the temperature to make the fish more active and this uses more oxygen and depletes the ability of the water to hold oxygen so we aerate to compensate, and then we overload with fish to make the tank look busier and add a filter so when the filter and aeration stop with a power cut it all goes to custard.
I wouldn't touch the filter, just start it up and get everything working again. It will find its own balance. If gonorrhea can remain viable on a toilet seat for days then your filter is probably OK.
Around here there are sometimes young ones born late in the year and don't have enough condition to hibernate. They are sometimes wandering about all forlorn and full of mange. We found one last year and gave it to hedgy rescue but they usually don't make it we were told.
I bought it off trademe me and it was sold as being OK up to two tubes at 40 watts but it is realy only suitable for that and not smaller tubes. They make smaller ones but don't seem to import them.
You will need a proper reptile UV lamp which is cheaper from a wholesaler. Can't tell where you are but lamp specialists are good if there is one near you. Heat from a ceremic heat emitter is best in my opinion as theey only give off heat without light at night. Put the heat emitter at one end so they have a cooler end if they wish. I don't like heat pads as beardies can't sense the heat on there underside and if you put enough driftwood they will be able to pick the place with the heat they like.
Or you can buy the fancy ones that create dawn and dusk as well on your flouros (I got mine off trademe). I think they were only suitable for 2x4ft tubes.
In the past I have used tea bags, peat, oak leaves, oak bark or driftwood and all with no problems. The brown water in streams from the west coast can be pretty good also--rainwater which has run through leaf litter.
The male fighters that are imported are kept in very small jars until mature and sold but the labour costs of water changes are a lot cheaper than here. When I was breeding fighters I made a tank within a tank and the inside one was divided into sections 80x80x200mm and the internal tank had a mesh bottom. To do a water change I lifted the inside tank and then let it fall back in to place---easy as. Males develop better fins if they are kept seperated but able to see other males.
Lance from Pet World Northlands has a great looking site next to Donna as well so there are 3 fishy stalls together. Haven't had a chance to look at the other stalls.
The wood will make the water more acid and that will put even more calcium into solution and make the water even harder. Calcium carbonate is almost insoluble in other than acid conditions. I have a tank with three LARGE chunks of marble and it has been good for many years, containing a mixture of community fish and plants.
The whole point of using medications is to kill things (diseases or parasites) if they were not toxic they would not work. A doctor once told me that half of the prescriptions they write are to treat the side effects of the other half they write. If it is a medication treat it with respect. If you don't wish to subject your fish or yourself to the presence of toxic chemicals then don't treat them. I prefer to treat mine when necessary using common sense and care.
They make terrariums with mesh lids at Bubble and Squeek in Stanmore Rd and would probably make a special if you wanted. They have made a couple for me where I provided the s/s mesh.