Water top off?

Yes, it will eventually make nitrates, but that's what you want. You want the tank to cycle: ammonia > nitrite > nitrate. If you have nitrates, that means the bacteria is doing its job. If you get a very small ammonia and nitrite spike, you're not going to be "breeding" much bacteria and when you start adding livestock you're going to have another ammonia spike.

I wouldn't use frozen mysis, simply because it's too expensive to be dropping in a tank with nothing eating it. You can use flake food if you want.

 

Thanks for the help! I think i'll try that, and then do a WC before adding fish.

 

Sounds like a plan.

 

Good info in this thread. One of the things that I'm most worried about it how to cycle my first tank. I've been doing quite a bit of reading, but hadn't run in to the shrimp suggestion yet. Make sense though

 

Boosted, I had never heard of it either, but I'd been out of the hobby for over 6 years. I used a small piece of raw fish instead cuz I had it on hand. Man, it sure spiked the ammonia like crazy! Ended up with frustratingly high nitrates too, and I figured I'd never cycle like that again...however, now that I've finally put fish in my tank (4 at once LOL) and got no ammonia spike, it seems to have been worth it.

 

Yes on all accounts, The shrimp will add nitrates, hence the need for water changes weekly (20%) and the monitoring to watch as your bacteria begin to grow and consume the nitrates, nitrites, and ammonia. These are the same bacteria that will consume the same nutrients that your fish will produce. The decomposing shrimp, (I would not bank on the mysis, not enough "gut" bacteria) contains the bacteria in large quantities. The decomp process gives them an initial meal.
But this whole process still takes time, give it a month minimum, IF all your numbers climb good and high, then fall off. Watch out for a multiple cycle. Nothing wrong with this, just a possibility. Understanding this process will help you diagnose problems in the future and head them off to avoid a dreaded and needless "crash".