Small nitrite spike, what should i do now

[Country joe]

I got rid of my 70 litre tank which was running a sicce external filter with about 8 cardinal tetras, I started up a new 125 litre using plants and wood, and substrate from 70 litre tank the new tank is now running an Osae biomaster 250 which I used the ceramics from the sicce, which filled one tray of the oase.
I transfered 22 cardinals from my 200 litre, which I now realise was a lot for the new filter. Two days later I tested the water, all was good apart from .5 nitrite, I did a 12% water change, and added one small bottle of Tetra Safe Start bacteria in a bottle, and up to that point I was dosing Seachem Stability. I left it 24 hours and did a water change today, and it's reading nitrite nil, I forgot to mention when I found the ,5 reading I cut the feeding right down to once every two days., today at nill nitrite I added seachem stability, and the fish and Amano shrimps look okay, so, what should I do now, that my test readings are good, used Nts labs test kits.

 

[TwoTankAmin]

Seachem Stabolity is a bottle of spores. The nitrifying bacteria do not form spores. On the other hand, Safe Start contains live nitrifying bacteria one of which are the nitrospira which, dependiing on the strain, either convert nitrite to nitrtate or they convert ammonia straight to nitrate.

Also, chloride blocks nitrite from entering a fish. Using a small amount of salt will keep fish safe. You can read about this in the article here on cycling. Look for Rescuing a Fish in Cycle Gome Wild. The article has step by step directions for how to know how much salt to add.