Hey Tokis, what part of Somerset are you from?
Any good LFS your way, not 1 good one in bristol really.
The only large chain lfs i know of near me is "Watermarque" in a town called Yeovil- it has a very good selection of fish, well over 200 tanks i would say, plus a lot of rare tropical, marine, brackish, sub tropical and colwater fish etc.
The staff knowledge there is pretty average though as far as lfs's go(i.e pretty poor), and they somtimes mislabel plecs and other rare fish, but other than that its pretty good- it also has a huge range of fish merchandise(i.e foods, meds, tank decor, plant stuff like CO2 systems etc), tanks(lots of tanks exceeding 100gals too) and ponds, garden stuff and other pets(mainly birds, reptiles like turtles/tortises, lizards, snakes, rodents, weird insects/bugs/critters) including a lot of other pet related stuff and some awesome display tanks

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I would really recommend it for everything fish or pet related you want to buy, its a huge place, but its not a place you would go to for good fish advise or info on the fish or animals they sell- and not a good place to go to go if you are prone to impulse buys as it has some very awesome fish and stuff there

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It has its own parking area outside, although not very large, i've never gone there and found no parking places so its ok- its quite out of the town centre though, you couldn't really walk there from the town centre due to all the busy roads and distance, so you really need to get there in a car

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Other than that i just go to my main local bog standard small lfs

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