Nitrites and ammonia test kits aren't needed going forward and are only really used in the initial setup of a tank. Nitrates could be tracked going forward, but I would take a look at a better test kit for that (Salifert). As for phosphates, switch it out for a Hanna ULR phosphate "egg" instead.
Looking at your progression, it doesn't look like you've been quarantining the fish. I would highly recommend that you do so for the remaining fish and consider qt'ing any future purchases. I would also recommend that you have a top over your tank with that list of fish. If you don't want to spend a ton of money, consider a DIY top, such as the one that chromis is holding a session for.
Looking at your progression, it doesn't look like you've been quarantining the fish. I would highly recommend that you do so for the remaining fish and consider qt'ing any future purchases. I would also recommend that you have a top over your tank with that list of fish. If you don't want to spend a ton of money, consider a DIY top, such as the one that chromis is holding a session for.