New 15g long startup

[pieceofreef]

Hi! New here and hoping to get some ideas on doing things correctly. I currently have a cycled 15g long that's been up and running for a little over 2 months. I've heard various opinions on the right amount of water to change and how often. Inhabitants atm are 1 1" clown, 1 hi fin red banded goby, and I plan to add a purple firefish next week. What should a good wc schedule look like? I do plan to add corals at some point and I know nitrates have to stay very low, which leads to my next question. On hand I have purigen and chemi-pure. Which would be best? I have an AC 70 running on this tank. Oh, no skimmer and no plans for one. Any input would be appreciated!

 

[terrypercula]

Weekly water changes of 10% should be fine. I've never used chemical pure so someone else will have to speak for that, though I've heard good things.

 

[zombiereefer]

any time i have a small tank setup i use chemipure the elite adds gfo use it its great