Is this possible with bitcoin right now?

[Was]

Say I have a Bitcoin based marketplace through bitcoind php and json
and in an effort to keep the blockchain clear of dust and relatively "small" transactions, could a user "commit" a certain balance that would be deducted once the balance value (say for example $50) is reached within the marketplace via a multi-sig transaction/contract.

The user could do 5 $10 dollar transactions with 5 different sellers etc

Or is this what Lightning network is?

thanks

Was

[hexafraction]

Why not implement a database of balances, and snacks deposits and withdrawals for buyers and sellers instead?

[tommorisonwebdesign]

Yes the bvest way to avoid clogging the blockchain with dust payments you could implement a balance which could be stored in a database and from there you could link your users to balances in the database with a JOIN query. It should not be too hard to do.

[Was]

Why not implement a database of balances, and snacks deposits and withdrawals for buyers and sellers instead?

Wouldn't be publicly audit-able