bruinsbro1997
Aquarium Advice Addict
There are plenty of reasons not to overstock, but here's the ones I have found most important and interesting, and frequently mentioned:
1. Just because fish are small doesn't mean they belong in a small tank. A betta is not going to have much room to swim in a small glass bowl you got him. Even the smallest five gallon will provide him plenty of room to swim and stretch out as he pleases. A cute baby pleco won't have enough room in there either, which brings us to #2.
2. Adult size of the fish isn't taken into consideration most of the time. For example, say you wanted to keep an adult elephant in your room. Sure, the elephant could fit, but it certainly wouldn't have much room for it to move. The same goes for fish. Yes, that tiny little common pleco looks cute in the store at two inches, but in two years that small, tiny cute algae eater is going to grow up into a two foot monster.
Also, its important to point out that stunting fish is possible when you keep big fish in small tanks. For example, if you kept a common pleco in a ten gallon all it's life, it would be stunted. Stunting happens when you keep a fish in a tank that's too small for it, and to adapt it stops growing and keeps its internal organs squished inside. Although small, the process is painful for the fish and can increasingly shorten their lifespan. Also, some fish don't stop growing. Some will keep growing regardless of tank size. A foot-long clown loach or bala shark or oscar isn't going to be very happy in a ten gallon, foot long tank.
3. Some fish are more active than others. A prime example is the zebra danio. Because they are hardy, active and easy to keep, they are commonly bought and kept in aquariums. However, keep in mind these are active fish and will need room to use up their energy. Keeping them in a tank smaller than what they'd like will leave them less room to swim around and more likely to be under stress. For our example, I would say a 20Long would be suitable for one, not a ten gallon like most people keep them in, because they have more room to swim and socialize.
Also, some fish are extremely territorial. For example, breeding pairs of convicts usually do not tolerate one another. In the wild, they have a lot of room to stretch and get away from one another, but in a tank there's not enough room for them to get away (unless you have a ridiculously large tank). This can lead to aggression, stress, and more prone to disease.
4. Fish poop and pee, and need to be kept in a big enough tank so that the filtration and bacteria can keep up with it. Mollies, for instance, have a huge bioload and are one of the messiest fish I've seen. Keeping them in a five gallon tank isn't acceptable because a) not only do they grow too big and active for a five gallon, but b) they have massive waste loads and can easily use up all your bacteria to process their ammonia into nitrites into nitrates. You need to keep a sharp eye on water quality if you want to try to keep fish that have big bioloads in small tanks, which is why water changes are so crucial; they help ease the bioload, especially in overstocked tanks.
5. It's just not that healthy. Having a "ticked-off tetra" is not something ideal for me or anyone else. Yes, fish actually can get angry. Angry Fish Inhabit Most Home Aquariums : Discovery News
These are just reasons why you shouldn't overstock a tank I came up with, but there are plenty more out there. If you have more, feel free to add to this thread
1. Just because fish are small doesn't mean they belong in a small tank. A betta is not going to have much room to swim in a small glass bowl you got him. Even the smallest five gallon will provide him plenty of room to swim and stretch out as he pleases. A cute baby pleco won't have enough room in there either, which brings us to #2.
2. Adult size of the fish isn't taken into consideration most of the time. For example, say you wanted to keep an adult elephant in your room. Sure, the elephant could fit, but it certainly wouldn't have much room for it to move. The same goes for fish. Yes, that tiny little common pleco looks cute in the store at two inches, but in two years that small, tiny cute algae eater is going to grow up into a two foot monster.
Also, its important to point out that stunting fish is possible when you keep big fish in small tanks. For example, if you kept a common pleco in a ten gallon all it's life, it would be stunted. Stunting happens when you keep a fish in a tank that's too small for it, and to adapt it stops growing and keeps its internal organs squished inside. Although small, the process is painful for the fish and can increasingly shorten their lifespan. Also, some fish don't stop growing. Some will keep growing regardless of tank size. A foot-long clown loach or bala shark or oscar isn't going to be very happy in a ten gallon, foot long tank.
3. Some fish are more active than others. A prime example is the zebra danio. Because they are hardy, active and easy to keep, they are commonly bought and kept in aquariums. However, keep in mind these are active fish and will need room to use up their energy. Keeping them in a tank smaller than what they'd like will leave them less room to swim around and more likely to be under stress. For our example, I would say a 20Long would be suitable for one, not a ten gallon like most people keep them in, because they have more room to swim and socialize.
Also, some fish are extremely territorial. For example, breeding pairs of convicts usually do not tolerate one another. In the wild, they have a lot of room to stretch and get away from one another, but in a tank there's not enough room for them to get away (unless you have a ridiculously large tank). This can lead to aggression, stress, and more prone to disease.
4. Fish poop and pee, and need to be kept in a big enough tank so that the filtration and bacteria can keep up with it. Mollies, for instance, have a huge bioload and are one of the messiest fish I've seen. Keeping them in a five gallon tank isn't acceptable because a) not only do they grow too big and active for a five gallon, but b) they have massive waste loads and can easily use up all your bacteria to process their ammonia into nitrites into nitrates. You need to keep a sharp eye on water quality if you want to try to keep fish that have big bioloads in small tanks, which is why water changes are so crucial; they help ease the bioload, especially in overstocked tanks.
5. It's just not that healthy. Having a "ticked-off tetra" is not something ideal for me or anyone else. Yes, fish actually can get angry. Angry Fish Inhabit Most Home Aquariums : Discovery News
These are just reasons why you shouldn't overstock a tank I came up with, but there are plenty more out there. If you have more, feel free to add to this thread