depends on ur budget.can go as low as 70 up to a few thousands.each with its own advantages.im a newbie also but been there done that

If 30x30,u can try fluval set. Quite cheap. But it uses the disposable co2 canister. Good for u to get a hang of it but if u can poke some extra budget, around 200 u can get a starter kit. How it last depends on how much u use. For 30x30 u might be running on 1 bps nly so its gonna last long

They look like pond snails and they multiply very fast. Best you catch those that you can spot and then get something that will hunt and eat those that you can't find.

What I've read before is that people use clown loaches or puffer fish to hunt snails. Some people also use assassin snails for the job. I guess the clown loach is the easiest to find. Assassin snail I've only ever seen it once in a shop.

yo, i personally have used puffer fish before. it will go and hunt all the snails/things that is crawling on the glass/plants including ur weaker fish. puffer fish will chase it around n bite its tail until it weakened and unable to swim, killing it slowly. well that is what i notice    always buy only 1 puffer because if you buy more than that it will boss around ur tank and put ur other live stock in danger lolz.
btw anyone have any idea on how to get rid of hair algae? its bothering me enough already. i have done my water change twice a week. lessen my lighting to 3 hours a day only. ensure co2 is enuf in my tank. but still the hair algae persists! everytime i do water change i will need to plug it off the rock + plants zzz... damn annoying

Dear Sifus,
I've just started my 2ft aquarium using DSM. Since plants use light for photosynthesis, what if i left my lights on 24 hrs without turning it off. Will it make the plants grow faster?