10 Things Never To Do With A Fish Tank

planted aquarium with 2 fish
Photo by Vassil

A fish tank can be the perfect decoration for your house. They are normally beautiful and can be a great distraction. Many people tend to learn and do some research on what needs to be done when owning a fish tank. The problem is many only skim through the basics such as how to set it up and how to treat the water.

Knowing that is all good, but there are some other things that you shouldn't do in order to properly maintain the tank as well as the fish inside. Let's look at some of these things:

Never do These Things

1. Put Untreated Rock or Driftwood you find lying around

One habit that many people tend to do is to add random driftwood or rocks in their fish tank. This isn't quite the best idea as the driftwood or rock might hurt your fish somehow.

If you pick an awesome driftwood, the best thing to do is to treat it first by boiling or soaking it for a few hours. To go a bit out of point, salt water drift wood can work well in a fresh water tank, no need to worry about that.

2. Mixing Random Fish in the Tank

It's not a good idea to mix random species of fish in your tank. This is because each species tends to have different levels of aggressiveness and they can become a bit crazy in the tank. Be sure to do some research and check which species of fish work well together as well as their water needs.

This will help ensure that the fish you place in the tank don't end up becoming the others' lunch. In addition, your fish ecology will cherish, thanks to that extra time you took to learn.

3. Thinking all Decorations are the Same

biorb fish tank with decorations
Photo by Stephaphonic

Again, not all decorations are the same; some can be pretty harmful to your fish. You need to take your time when picking the decorations for your tank. The things to take into consideration are maintenance and your fish. You need decorations that wouldn't make it too hard to clean your tank.

What you need to do is pick the decorations out carefully. Check and make sure that the decorations contain no toxins or parasites that could be harmful to your tank. As a general rule, don't add glass, plastics, coins and any sort of ceramics.

4. Beach Sand in your Tank

Sand tends to look good in the aquarium as a substrate and we agree with that. What you have to be aware of is that it can be harmful as well. Beach sand looks nice, but tends to be polluted and might contain too much salt which could be harmful to your fish.

With that said, you need to know that there are different types of sand. Among all the types, we'd advice you to use silica sand which works better at the bottom and is good for your tank.

5. Not Washing Your Hands Properly Before Placing Them In The Tank

It's easy to say that we're far reaching with this one, but the truth is that in the long run this could be an issue. This is more of a problem when you have cream, soap residue or sometimes lotions that are not properly washed off your hands. Constant exposure in the fish tank can cause complications for your fish.

6. Not Changing the Water in a Long Time

This should be obvious to many, but it's important that you change the water partially from time to time. This is because the fish normally release waste in the water. A lack of change could be harmful to them. In addition, it will also make maintenance of the tank harder. Be sure to change the water partially from time to time.

7. Overfeeding Is A Problem

Be very careful when you own fish, don't overfeed them. This is a mistake that many beginners tend to make. Feeding your fish too many times can cause issues. It's much better to feed them in small quantities.

Many people tend to overestimate the appetites that fish have. The creatures are a lot smaller and don't need to eat as much. Eating a lot can cause accumulation of waste which isn't good. Again, be careful and feed them in small quantities.

8. Too Many Fish In One Tank

It's important to always remember that the number of fish in the tank needs to be monitored. Don't add too many fish in one tank as this might lead to problems. Like animals on land, fish also tend to have territorial needs.

Too many fish in a tank might cause fights for territories. In addition, the bigger fish are going to devour the smaller fish and there might be a spread of illness among them. The best option is to place 1 inch of fish per each gallon of water.

9. Changing All the Water at Once

As much as it might seem better to do this, it's not a good idea. Changing all the water at once can do more harm than good. Bacteria is a reason as not all bacteria are harmful, some can be good for the fish ecology. By changing 100% of the water, it can eliminate these useful bacteria from the ecology, so treat this information with care.

For more information, you can visit this link: https://aquaristguide.com/how-to-cycle-your-fish-tank/

10. Water Ager Is a Must

container of aquarium water ager

Water ager is important for your fish tank especially if you're going to be adding tap water to the tank. Tap water can be a problem as it contains chlorine. Chlorine is harmful to the fish and can be damaging to the ecology. Water ager helps to neutralize the effects of the chlorine and is definitely a great addition.


A fish tank is a good addition to the decorations of any establishment, be it a house or office. With that said, it's important that you take good care of it and take note of the points above to ensure the long-term maintenance of your tank and the fish inside.

Author Bio:

Toby Sanders underwater diving

I'm Toby Sanders with more than 15 years of experience in aquarium sector, I'm totally passionate about creating Aquarist Guide blogspot. I enjoy sharing all of my knowledge to help you guys effectively build your own tank. I believe that when you find the easiest way to raise your lovely fish successfully throughout my blog, you will definitely fall in love with fish keeping more than a popular hobby.