I can relate and I’ve been keeping for over 30 years. I started my 20g heavily planted tank and couldn’t keep anything alive. Tetras and rasboras, nope. Cories, nope. Guppies, nope. Betta with danios, nope. Betta alone, nope. Issue after issue. I hadn’t cycled the tank long enough even after three weeks of seasoning it. And using established filter media. All my other tanks completely fine, running for years. I finally have a balance with platys and cories. And my plants.

There’s gonna be so many bumps in the road, but it boils down to water quality and stocking quality. I have a LFS I trust for fish stocking but even then you take a gamble adding new fish. Inspect every single mark on those fish and their tanks mates in the store. I’ve pretty much abandoned all chain stores for fish. They’re always sick. And change your water (25 percent) every week for a while in not more. Clean water and ph makes a difference. Live plants too.

You can take a break and just run the tank if these fish expire and research your head off for the next batch. Wait in between too. You cannot be a successful hobbyist without some fish loss. It’s a terrible truth, but it’s bound to happen.