It does appear to be rather difficult recently. I know that vivexotics previous range were larger dimensions and they've for some reason reduced the size. I am totally lost as to why, it would make a huge difference both in general size to manoeuvre and to maintain proper temps.
Hopefully someone will be able to help, I haven't been viv hunting for a while. I'd suggest contacting some viv builders as their prices should be fairly cheap for a 4x2x2, usually of better quality too.
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