7 Beginner Aquarium Mistakes To Avoid (Live Plants)

By Billy | Updated: March 18, 2022 | Planted Tanks

I made a lot of beginner aquarium mistakes that I could’ve avoided. I wish I had a simple resource I could reference in the beginning of my journey.

So, I put this together to make you aware of what I did wrong.

My first mistake was…

7. Slow Water Pour

Lay down a plastic bag or saran wrap before you start pouring in your water. This will help control your water’s clarity. I originally laid my substrate, placed my plants and poured water in. This was a big mistake because since there was no barrier, the water pressure made lots of the substrate particles suspend.

Key takeaway: Lay down a layer of plastic between your substrate and water pour. The slower the pour, the better. Be patient.

6. Let It Cycle

The day I got my aquarium, I immediately went to my local pet store, bought plants and some neon tetras. I was very impatient and didn’t let me my tank cycle and grow healthy bacteria. As a result, one of my neon tetras died within one day.

Key takeaway: Have patience and let your aquarium’s ecosystem cycle.

5. Small Tank

My initial thoughts were that a smaller tank would be easier for a beginner. This is not the case because if there’s anything that infects your water, it’ll spread faster. A smaller tank is harder to regulate. I would’ve started with a 10 gallon aquarium. Ya live and learn.

Key takeaway: It’s harder to control the water parameters in a smaller aquarium. A bigger tank is easier to maintain.

4. Too Much Substrate

My original mindset was “the more, the better”. Specifically with substrate. For my 5 gallon aquarium, I ended up laying down 2″ of substrate. But after more research, I learned that you realistically only need about 1/4″ of substrate for the majority of live plants to thrive.

Key takeaway: Less is more when it comes to substrate.

3. Upgrade Light

I was so excited about having live plants in my aquarium and didn’t realize how much lights play a role. It wasn’t until two of my plants died and I began researching.

The solution was buying a new light and some fertilizer.

Key takeaway: Less is more when it comes to substrate.

2. Regular Water Changes

I was lazy about doing water changes. I probalby only did them once every couple months, which made it harder to control the parameters. I specifically had an algae issue, which could’ve easily been avoided if I did a 10-15% water change every week.

Key takeaway: Save yourself the headache and make it a priority to do a 10-15% water change every week.

1. Too Much Food

It’s tough to figure out how much to feed your fish, especially when you’re a complete noob. A reference I’ve heard is to look at your fish’s eyeball and that’s the amount of food you should feed them daily. Or feed them enough for them to eat for two minutes. If you overfeed them, that food will float to the bottom and could cause necessary bacteria.

Key takeaway: Don’t overfeed your fish. The uneaten food will float to the bottom and can cause unwanted water parameters.

Bottom Line

Building your first aquarium doesn’t have to be complicated. Avoid these beginner mistakes and you’ll be well on your way to a flourishing fish tank.


I've had a fascination with aquariums since a young age. Recently, I built a 5-gallon planted tank. My goal is to share my journey to help make yours easier.