So you’re thinking about setting up a fish tank, or maybe you’ve already got one and you’re realizing it’s more than just filling it with water and tossing in some fish. Either way, keeping an aquarium going can be super rewarding—but also kinda tricky if you don’t know what you’re doing. Here’s a list of tips I’ve picked up along the way that’ll help keep your fish happy and your tank from turning into a smelly swamp.

1. Pick the Right Size Tank—Bigger Is Usually Better

I know small tanks seem easier, but trust me, they’re actually harder to keep stable. A 20-gallon tank is a solid size if you’re starting out. Gives the fish some room and keeps water changes from becoming a nightmare. Plus, mistakes don’t mess everything up as quickly.

2. Don’t Skip the Cycling Step

Before you throw fish in, you gotta “cycle” the tank. Basically, that means waiting a few weeks (yeah, weeks) while good bacteria grow to handle fish waste. It’s boring, but if you skip it, you’ll end up with sick or dead fish, and that sucks.

3. Get a Decent Filter

Not all filters are created equal. You want one that does a few different types of filtering—mechanical (like trapping gunk), biological (bacteria stuff), and chemical (like removing smells and toxins). Spend a little extra on this if you can. It’s worth it.

4. Check Your Water Often (More Than You Think)

Water can look clear and still be bad for your fish. Test your pH, ammonia, nitrites, and nitrates regularly (once a week is good). Temperature too—most tropical fish like it somewhere between 74–80°F.

5. Water Changes Are a Must

Don’t just top off the tank. Do partial water changes, like 15–25% once a week or every other week. It helps remove stuff that builds up and keeps your fish healthy. And always treat tap water before adding it in—chlorine will kill your fish.

6. Go Easy on the Food

It’s fun to feed them, I get it. But too much food = leftover gunk in the tank and unhealthy fish. Only feed what they can eat in a couple minutes, once or twice a day tops. If you see food sinking to the bottom, you’re probably overdoing it.

7. Make Sure Your Fish Get Along

Some fish just don’t play nice with others. Before adding new ones, look up if they’re aggressive or territorial. Even peaceful fish can get stressed out if the tank’s too crowded. More space = less drama.

8. Don’t Overdo the Light

Fish need a day and night cycle. 8–12 hours of light a day is enough. If you leave the light on all the time (or your tank’s by a sunny window), you’ll probably end up with gross algae everywhere. Use a timer if you’re forgetful.

9. Clean Smart, Not Too Much

Yes, you should clean the tank, but don’t go overboard. Clean the glass, vacuum the gravel, but when it comes to the filter, just rinse it in tank water—not tap water—so you don’t kill the helpful bacteria living in it.

10. Watch Your Fish

Like, actually look at them every day. Are they swimming weird? Got spots? Hanging out at the bottom looking sad? Catching problems early makes them easier to fix. Plus, it’s relaxing to watch them do their thing.

Final Thoughts

Fish tanks aren’t just decorations—they’re little ecosystems that need care and attention. It takes a bit of learning (and some patience), but once you get the hang of it, it’s a pretty chill hobby. Follow these tips, and you’ll be on your way to a tank full of happy, healthy fish.