First Saltwater Tank: Nitrites came back after adding cleaning crew

[SaltySmith]

Hi Everyone! First time poster here. I purchased a WaterBox 20 gallon cube about 5-6 weeks ago and have been loving it. This is my first saltwater tank after keeping freshwater tanks for over 10 years. I am loving the process. I have a situation that I would like some advice on. I just finished cycling my tank last week, which was week 5. My nitrites were finally at 0 and my nitrates were at 10. I went to my LFS and got a cleaning crew to test to make sure things were going to survive before adding in fish.

The inverts have been doing well, cleaned the algae that grew during the cycle pretty quickly. I have been adding in some fish pellets every few days to keep a food source going for them. Well, after about 4 days of adding the inverts, I was thought I was ready to add in some clowns. Well, when I went to my LFS, I had my water tested, here were the levels:

Salinity: 1.025
Ammonia: 0
Nitrite: .5-.10
Nitrate: .20ppm

Two questions:
1. Is it normal for the nitrites to spike again after adding in your first inverts or fish to a freshly cycled tank?
2. Should I do a water change? or wait a few days for the nitrites to come down and then do a water change and add clowns?

Thank you everyone for your help!

 

[jsker]

Hello, welcome R2R!!

 

[Sebastiancrab]

Welcome! Make sure you are not using API test kits. I would test again and then take a sample of your water to your LFS and have them test it. If you are cycled, it won't hurt to do a water change and add your new fish. Go slow, add fish slowly to build up the bioload. Good luck!