Yes, this is enough. So if you bought some amount once in a single tx, then it is enough to keep it open for day or two (actually until you get a PoS block(s) solved) each ten days since you got the coins. Remember, that each block splits the input into two different, so next time you should wait for 2 blocks, then for 4 blocks, e.t.c. At some point when the resulting inputs will be too small the walled should merge them into a single one.