I could see this being a decent little game, but there is just not enough resources given out, it's geared way to strongly as a pay to advance.
As someone else said you get the same treasures from red or green, the water goes down way to quickly and in order to upgrade things to keep up with the level progression you have to buy.
Nice game, it's a shame it's totally geared to pay or don't play though. the amount of res and time needed at such a small level or time played is insane. I can see myself (and tons of others more than likely) leaving the game simply because it's either pay or don't play....I mean wait for ever