The problem is I'm on a time crunch today. I wound up mixing it using a jar and tank water. I don't have rodi here. Only spring water which in retrospect I could have used. I only added half a cup for now. Hopefully I will find my refractometer tonight. I'll have more time to search then.Definitely don't add it behind the filter pad; it won't work- I've tried it before a long time ago during my earlier ventures here. If you really don't want to wait until the next water change, I would go and get a small tub/big jug, put some freshwater (bottled or RODI) and add a load of salt in it. This is what I do when I want to raise my salinity up a point- just add a ton of salt to a small amount of freshwater and pour it into the filters. I can't really tell you how much; I don't know your tank well enough to eyeball it and I use Reef Crystals. Check your salt level in a few mins and go slow. Salt, if it lands on coral, will burn them, so you want to make sure it's fully dissolved.
On that note, if you're using tap water, don't. Use RODI or distilled/bottled.
I would highly recommend some wave makers or pumps; you can get one or two jebao wavemakers for not much money and it'd be fine. Flow is extremely important in reefs- I like running as much flow as my corals can tolerate without being upset. This prevents detritus buildup and keeps algae low.
I hear you on macros in your display- I have some red gracilaria in my nano that doubles as a phosphate remover and a pod haven.
Carbon is good- whenever I have an upset coral, I always replace my carbon first if it's been awhile (as in a month or two). If that doesn't work, I dose a little bit. Since I run an LPS/softy dominant reef, Purple Up and some trace elements is all I do. 99% of the time that takes care of it.
Actually there isn't much Cyrano in there, mostly it's some other type that's harder to get off the tank.
Well now that I'm not doing seahorses I'll give upping the flow a go. I've got a spare power head on hand that I can add in.