Nice choice for a first time reef aquarium! (I'm a bit biased though )
Couple of things that you may want to consider as the tank grows:
- The IM filter socks are pretty bad in my opinion, they clog up in a couple of days and then the water just bypasses them completely and goes through that side of the tank without being mechanically filtered. As it fills up and causes water to back up, it's going to cause your other overflow to take in more water as the water flow resistance will be lower on that side. This will cause the side with the filter sock to sometimes go slack with little to zero flow, meaning if you have a skimmer also on that side that it will no longer be working to remove nasty stuff from all of the tank water. Right now it's not that big of an issue since you don't have a skimmer on the tank. Just keep an eye on that filter sock though and clean it often.
- I use two IM Custom Caddys on my tank. The stock media racks are junk and you should replace them eventually if you're still using one of them. I usually put two cut to size pieces of filter floss in the top two sections with either Chemipure Blue Nano on the bottom or phosphate reducing pads. Side note: GFO and Bio-pellets are usually too strong for nano tanks and will cause more problems than they solve, in my experience at least
Couldn't agree more, the stock baskets are terrible and the socks are even worse. Get the custom caddys and use some sort of floss or medias is you wish. Personally I only use the blue/white floss and put a cut rectangle on every level, usually only the top gets gunked up.