Help with 20g frag tank

Hi,
Im setting up a drag tank and am in the process. I'm wondering if I should use some kind of slimmer or aquaclear. I have a main tank that's 60 gallons I thought I could start the tank off with water from. I added some Pieces of LR and will put a damsel inside. My lights are some t5 HO . I am looking for growth and have a lot of zoas in there right now and other random coral but I think I really want to grow sps in there. What color bulbs would you recommend for best sps growth with my t5's . It's a 20 long and I can keep sps pretty close to the top near light in case intense lighting is an issue. 3 10k and 1 blue? 2 10k, 1purp, 1 blue?
Also, what should I do for further filtration? Can I make water changes weekly with new batches of saltmix and be fine? Would I benefit for an aquaclear.... Or is that pointless? Also should I test calcium and kh daily to see how much I need to add to keep the tank stable? Sorry for the fa paragraph I hoPe someone can help me thanks.

 

any thoughts please. im testing both main tank and frag tank water at LFS today. probably come home with a fat aquaclear to stick on my frag tank and call it a wrap.

 

With one fish I would say a skimmer is not needed with weekly water changes. No need for the aquaclear unless you wish to use carbon. Growth would be best with your first bulb combo and would be more than sufficient for SPS. I would test weekly and chart it so you know how much is used. Test right before the WC and an hour or so after the WC so you can see how your salt changes your parameters. Then after you have a weeks worth of data divide the difference by 7 and add that much daily for your dosing.

 

OG ty.