1. Tips for Peaceful Fish (How to keep fighting at a minimum, identifying aggressive breeds etc)

Tips for Peaceful Fish in Your Aquaponics System

If you’ve ever had an aquarium, you know that one of the most common reasons people give up on them is fish aggression. Fish appear to be so peaceful in the wild, however, so why is it so common to find them fighting in the tanks?

Aquaponics is no exception, and you will undoubtedly encounter fish aggression if you place your fish in the tank without the proper research. In the wild, there are many things that naturally prevent this aggression, and there are many precautions you can take when setting up your system. Take a look at the tips below, and you’ll have a peaceful tank in no time.

1. Find out if your fish are aggressive; if in doubt, assume they are. While some species can be added a few at a time to an aquarium or an aquaponics tank, aggressive fish should be placed in the water at the same time. Because the fish will try to establish their own territory within your tank, it is best to allow them to do this simultaneously. Otherwise, you may encounter a conflict between a fish whose territory is already established, and a new one trying to “take over.” This leads us to our second tip.
2. Provide them with territories! This is one of the major factors in the wild that is suddenly missing in a tank, and it’s a major contributor to fish aggression. If fish have nowhere to hide or claim territory, they will continue to battle and chase each other in the water. You can place a few large, smooth rocks in the tank that the fish can hide behind, or you can use other naturally occurring “ornaments” that provide hiding places for fish to establish territories.
3. “What if I already have fish in my tank, but I want to add more? Are they certain to fight?” Yes and no. If you simply add new aggressive fish, or add fish to an aggressive tank, but take no precautions, then yes, they will likely fight until one of them is floating. However, you can try a number of tricks proven to reduce aggression, such as rearranging any large rocks or ornaments. This “resets” existing territories, meaning all fish will be establishing territory at the same time, as if they were added simultaneously. If you only have one or two fish existing in the tank, you can use a mirror (on the outside of the tank) to distract them while your new fish establish their territories. They’ll be occupied with their own reflections, freeing up the tank until the new fish is settled. It’s worth noting, however, that rearranging is usually a better option, as sometimes the new fish can become preoccupied if they make their way over to the mirror as well. This can be frustrating and time consuming, even though the end result is usually a peaceful tank.
4. Ensure adequate feeding, and if possible, add an alternate food source. Fish are naturally quite food aggressive. After all, have you seen the way they rush to the top when they recognize it’s feeding time? If food supply seems scarce, they will inevitably turn to, or rather against, each other. This leads to nipped fins and eventually stress and injury. The best way to prevent this is to provide an alternate feeding source, such as some dry seaweed. In aquaponics, however, many people like to know exactly how much and what their fish are consuming, as the fish waste contributes to the system’s bacteria. Too much could lead to the need for frequent cleanings. If you aren’t comfortable adding an extra source of food, simply monitor your feedings and make sure your fish aren’t still searching the top of the tank after the food is gone.
5. If your aquaponics system is established, but aggression has begun after the fact, consider the tips above for rearranging your tank, but temporarily remove your fish during the process. This can completely rearrange the social structure of your tank, and a fish who was once the tank bully may become calmer. In addition, it may be helpful to reintroduce the fish to the tank in the order of “calmness,” allowing fish with less aggression a better chance at establishing territory first. You should be careful to avoid simply adding one fish at a time, however, as it can become bullied while establishing territory by itself.
6. Control algae. It may seem silly, but fish will claim territory even if it’s a small patch of algae. After all, to them, this is technically food, and they will guard it in a very Darwinist sort of way. Keeping the tank clean will eliminate this possibility.

In conclusion, it may take a few tries of arranging the tank and removing and adding fish in order to get all of the tank bullies to behave, but it is possible to have a peaceful tank in aquaponics. While many fish can be more aggressive toward their own species and fish of similar size, ensuring they have enough space in the tank, and enough territory to claim, is a great start at preventing aggression.