This might be a little long, and Im also new here, so please bear with me cause im so confused.
So I keep getting weird readings from my API kit and I cant work out what's going on.
First, some details: I have a 15 gallon with a betta and 3 panda cories (im working on getting a few more). My tank was cycled about a month ago after doing careful fish in with my betta (he was perfectly fine and still is btw) and after 2 weeks to my surprise it showed good readings for about a week or so after that.
I then proceeded to get 6 Panda cory but 3 didnt make the journey home from the fish store
(in hindsight, it would never have been a good idea to intro all 6 at once maybe, but I'd still have preferred to move them not have them die). But the 3 remaining have been in the tank for about 2 weeks now and they look really happy.
I was using API quick start to boost my bacteria upon adding the cories and as expected the ammonia rose a little so I water changed and dosed API ammolock, however I didnt realise how bad it was for the bacteria as i researched my sudden 8ppm reading. I was told the ammolock gives that false reading and binds the ammonia so nitrites cant eat it (they were still at 0ppm). So, I did a 90% water change to get most of that chemical out and swapped to Amquel Plus.
The next day, I got excellent readings: 0ppm ammonia and same for nitrite and a 5ppm nitrate. So i thought this was great and my issues were solved. Wrong, as the next day I was up at 2ppm ammonia again. I dosed Amquel after a water change again. Next day, same result. So I quit amquel for now and just kept on water changing to keep ammonia down.
2 days ago I had 2ppm ammonia and 0.25ppm nitrite, so i thought the cories had induced my tank to re-cycle and I also did a water change. But then yesterday I tested expecting the same and no, I had 0ppm ammonia and nitrite and again, 5ppm nitrate. So I felt good but suspicious. I was hoping for the same today but no again, im back at 2ppm ammonia and 0.25ppm nitrite.
Meanwhile, my betta and my cories are acting perfectly normal. I reduced their feeding as I usually feed my betta 2 times a day (3 or 4 hikari gold pellets each time but im working on getting bloodworms to vary his diet) and I was feeding my pandas a tiny pinch of Fluval Bug Bites which they eat like their life depends on it. I stopped feeing them the bug bites on the regular as they seem to eat organic matter (?) off every surface in my tank (wood, leaves, rocks, even my betta's floating log) and so i do it every 2 days now incase it is them pooping too much. My betta is down to once a day for now (dont wanna stop fully atm bc he has a minor wound and i want him to keep his strength up to heal well - its been three days and hes still very active tho and eating)
Anyone got any idea of whats going on? I just need to fix this and understand it so i can prevent it.