Hi Jules,
Regarding breeders, here's a list of UK breeders, and there is a Hermann's breeder listed in Brighton:
https://www.tortoise-protection-group.o ... section=44
I don't know them personally, but it is always better to buy from a breeder, as almost all tortoises sold in pet shops in the UK (there are some exceptions) are imported from breeding farms abroad and the stress of travel can cause flare-ups of parasites, and it generally isn't good for them. I don't know anything about the Birds of Prey centre, and it might be fine, but I would definitely ask where the tortoises come from. I do think that buying direct from a breeder often means you get good after-sales advice, as they want their babies to find good homes and have a healthy life.
Here is a link to a care sheet for Hermann's tortoises:
https://www.tortoise-protection-group.o ... 014New.pdf and here is a link to an excellent Hermann's site. Chris Leone is probably the world authority on Hermann's, and there is information here about sub-species, care, etc. He is based in the USA, and the care advice differs a little from what we practice in the UK, but it's only in tiny areas and is generally very authoritative:
https://www.hermannihaven.com/
That is great that you are designing your own table. If I could make a few suggestions -- first of all make it as big as space will allow. Tortoises need quite a lot of space, and although a smaller table -- say 4' x 2' is fine for babies and maybe some juveniles, the tortoise will need more space as it grows, so if you get a big one to start with then you won't need to upsize later.
Secondly, regarding your light fixtures -- it is really advisable to have a set-up where you can raise and lower the bulb that provides heat and light, in order to increase or decrease the temperature in the table. I have mine hanging from an overhead arm, but it is on a chain and I can raise and lower the chain as necessary. Temperature is absolutely crucial to tortoises, and the temperature in the table will vary depending on the temperature in the room, so on hot days you need to raise the lamp, and on cold days lower it.
Thirdly, if you're designing a table, I would definitely consider having a second level in it. It's a good use of space and tortoises love running up and down the ramp to the second level to see if there are any treats up there for them. I've attached a photo of my table to give you an idea. If you're short of space, you can even have an 'L'-shaped table going round a corner. The space under the second level functions as a sleeping area, but I wouldn't make the second level very big (just big enough for the tortoise to go up there and find some food) as it will be dark under that level and therefore the space is a bit wasted if the tortoise doesn't use it much (I made mine a bit too big and would reduce the size if I were doing it again), and also tortoises like a small snug space to sleep in, rather than a large area.
Finally, tortoises really benefit from being in a secure area outdoors as much as possible, as the UVB from the sun is of a far higher quality than anything we can provide artificially indoors, so do consider that in due course.
Hope this helps, and do come back with any more questions -- and best of luck in finding a really lovely tortoise to welcome into your home.
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