Day 9 to 21..... I added a seasoned sponge filter to combat ammonia on day 9 but had to move them to a bigger tank on day 16 as it was clear to me so many had survived, I needed to up the filtration, drastically. I added another seasoned sponge filter, 2 x small LOW FLOW powerheads with filter floss and some bio home ultra media and a bag of small rubble from my main systems whilst still maintaining water quality via 25% water changes every other day.