Fear of failure...

[LordJoshaeus]

My concern, again, is with the salinity. While these fish can handle up to 40 ppt, that's simply far higher than any aquarium keeper would maintain, and likely not good for the fish long-term.

I did a quick search, and it looks like most people are keeping these fish in a brackish environment with a salinity of about 1.002 to 1.017 SG, and that's going to be too low for softies and other typical marine critters.

I think you need to run the tank like a brackish water tank for these fish, and then embrace the few plants and other things that can live in brackish conditions. Or, consider running a more typical full marine tank, but go with different fish.

My decision is to go ahead with the saltwater tank, but I'll also set up a 10 gallon, 20 ppt brackish setup for the rainbow fish (which I already have, so they are my first priority). Any suggestions for other fish that would be comfortable in a 10? And should I set the brackish tank up with dry rock like I would a saltwater tank?

 

[Acro Junky]

All greats were made through failure. You will 100% fail, guaranteed. What will make your tank great is how you over come the failures! You being scared of failure is the first great step to making an amazing tank! You got this!

 

[exnisstech]

You got this. The only advise I have is keep it simple. Don't get caught up in all the hype about controllers and automation or dosing this and that. There are no miracles in a bottle. Algae is not an evil demon and often we have to learn to coexist. Don't expect results like you see on ign and YouTube etc. Those instill still false hopes and IMO never show the real deal including all the struggles.
Opps almost forgot, don't let anyone talk you into a redsea tank

Few examples of simple.
Reefer 170 maintained with water changes and ESV 2 part. Socks and no skimmer.

180g ran six years on WCs and kalk to maintain alk and calcium. Skimmer and socks.

Reefer 300 AFR to maintain alk and calcium. Very random 2g WCs. Reefmat no skimmer

I'm an advocate for keeping it simple especially when new. Once you master simple then you can experiment using some of the higher tech gear.

 

[Fish Fan]

My decision is to go ahead with the saltwater tank, but I'll also set up a 10 gallon, 20 ppt brackish setup for the rainbow fish (which I already have, so they are my first priority). Any suggestions for other fish that would be comfortable in a 10? And should I set the brackish tank up with dry rock like I would a saltwater tank?

Yes, I would use dry rock in a brackish tank too, it helps keep the pH up for those animals.

For a 10 gallon marine tank, your fish choices are a bit limited, but I would for sure get a Goby and pistol shrimp pair. These guys would live together down in the sand and under your rocks, and are pretty cool to watch them do their thing. They work together to build and guard their burry, and they will hide in it together is there's any perceived danger about. Then, you could probably add another fish or two that are more out in the open swimmers, like maybe a Damsel or the Dottyback.

 

[breathing underwater]

You got this! I would just second a couple of things already said: buy a nice chunk of live rock. Grapefruit to cantaloupe sized is plenty for a 10 gallon to start, pounds don't matter. You can add more, or work in dry rock over time. This base for your ecosystem will do wonders.

Second, topoff/salinity. Use a refractometer to get it right, and either an ATO or manually every day to maintain your water level. Unstable salinity is one of the few things that will really hold you back. Everything else can be optional. An occasional water change takes care of anything else at this level.

From there just have fun! I had a great little 5.5 gallon with just inverts and tiny scraps of coral from the $5 bin at the LFS. Had some basic no name clip on reef light I found for cheap. Eventually I added a single blue damsel, which was bulletproof.

My wife still mentions how much she loved that tank, and this is after multiple tanks including the current 130 gal full blown acro reef.