Instead of a less expensive fish, start with a hardy one - that's my advice. I wouldn't recommend damsels, though, as they can be a bit of a handful in small tanks, and they have a tendency to terrorize the other fish.
When it comes to stocking your tank, I'd say the clean-up crew should be the first in. You can add these guys once your cycle is complete. A typical clean-up crew consists of crabs and snails - they're great for keeping your tank clean. Shrimp, on the other hand, are a bit more sensitive, so it's best to wait a bit before adding them.
RO water is a good idea, in my opinion. It's basically super-purified water that's free from all the impurities and chemicals you'd usually find in tap water. Tap water can be a bit of a problem, to be honest - it often contains high levels of nitrates and phosphates, which can lead to algae problems. And let's be honest, tap water isn't exactly ideal for coflakes either.
Just be patient, that's the key. I know it's hard to wait, but trust me, it's worth it in the end.
seeking guidance on marine fish for beginners
Re: seeking guidance on marine fish for beginners
Just got my tank and I'm literally buzzing to get started, think I'll be spending the rest of the day unpacking and setting it up. Can't wait to share my progress and I'm sure I'll be back with loads of questions - bear with me, I'm a total newbie to this marine aquarium lark.
Re: seeking guidance on marine fish for beginners
My tap water seems to be alright, I've tested it and it comes out with zero ammonia, nitrites, and nitrates.
Re: seeking guidance on marine fish for beginners
I'm gonna try my luck with tap water first, see what happens.
Re: seeking guidance on marine fish for beginners
Can't wait to see it all set up, show us a pic once you've got it going