Ok. I know this is A LOT of links but pleeeaaaseee if you have the time, just flick through them and could you just tell me if it looks alright, or if you have found any problems with the products, or any cheaper places to buy them.
Tank-
http://www.swelluk.com/aquarium/fish-tanks-404/juwel-aquariums-407/juwel-vio-40-aquarium-white-351052.html
Substrate-
http://www.fish-fish-fish.com/hugo-kamishi-black-aquarium-gravel-8kg.html?store=default
Gravel cleaner-
http://www.swelluk.com/aquarium/cleaning-equipment-18/gravel-cleaners-142/juwel-aqua-clean-gravel-cleaner--349018.html
Thermometer-
http://www.amazon.co.uk/Aquarium-fish-tank-Precise-thermometer/dp/B002YY8Y7G/ref=cm_cr_pr_product_top
Heater-
http://www.surreypetsupplies.co.uk/juwel-heater-50-watts.html
Water testing kit-
http://www.amazon.co.uk/API-Freshwater-Master-Test-Kit/dp/B000255NCI/ref=sr_1_1?ie=UTF8&qid=1327233775&sr=8-1
Water dechlorinator-
http://www.amazon.co.uk/API-Freshwater-Master-Test-Kit/dp/B000255NCI/ref=sr_1_1?ie=UTF8&qid=1327233775&sr=8-1
Net-
http://www.petsathome.com/shop/aquarium-fish-net-fine-blue-in-7.5cm-12.5cm-and-20cm-sizes-by-marina-25636
Algae magnet-
http://www.amazon.co.uk/MAG-FLOAT-floating-magnet-aquatic-cleaner/dp/B004FSEBYE/ref=sr_1_2?s=pet-supplies&ie=UTF8&qid=1327346039&sr=1-2
Tank cleaner pad-
http://www.petsathome.com/shop/tank-cleaner-pad-by-pets-at-home-28482
I was only allowed 10 links, so i had to get rid of my ornament, background and plant links, but the plants are just silk ones. In case it matters, i plan to keep a single male betta.
thank you soooo much! 
sorry, i realise that people don't want to look through masses of links (i wouldn't) so basically, its a 30l tank, 50w heater, API water master test kit, juwel gravel cleaner, Prime by Seachem water dechlorinator and a 3 inch net. Sorry to those first 4 answers!
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