
Hello Little Fish © etva
This post is a collaborative effort between Katheryn Brandy, who wrote the article, and Etva, who provided the fishy photos.
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It's amazing I still have a fish aquarium. My first experience with fish was not good. Within a week of setting up my tank and adding my fish I had some of the fish die. When I went back to the store, the clerk told me I needed to correct the ph and sold me a bottle of chemicals. I dutifully put the chemicals in and then my fish got ick.
I went back to the store with my new problem and they said I needed a bottle of a new chemical to cure the ick. Back home I went and again, added the new chemicals to the tank. My fish got fungusamongus. Wearily I took my quickly thinning wallet back to the store and they said I needed a bottle of this new chemical guaranteed to cure all the other ills.
And on and on it went until I had no more fish to overmedicate. Just a very expensive (for me) empty tank and no money.
I threw away all of the chemicals (and the store went bankrupt) and started over. I want to save you the trouble I went through.
The first step toward fishy success is to firmly implant the concept of a closed environment in your mind. It's the key to a successful tank. Here's the set up.

Beware the Fish Apocalypse from Fungusamongus © etva
The apocalypse has happened. The only safe environment you can live in is a self - contained room - 10'x10'. Oxygen enriched air comes in at a fixed rate and oxygen depleted air is removed at a fixed rate. That rate is set up for 3 people to live comfortably within our enclosed space. You could put more people in, but the good air would get used up quicker and while the people might live - it would not be healthy and they will be more susceptible to disease.
Waste is deposited in a non flushing receptacle and must be removed at a set rate. If you have fewer people in the room, you can go longer between removals. If you have more people in the room - the receptacle overflows and the air will become tainted that much quicker and you have to remove the waste more frequently.

Dirty Water; Can't Breathe © etva
Tainted air leads to a faster rate of oxygen depletion and chance of disease occurring more readily. If you feed the people more than they can consume - more waste is produced and more food lies around and rots which can also taint the air. The key to these people not only surviving, but remaining healthy is to maintain their closed environment and the factors that could pollute that closed environment.
1) How many people are in the room
2) How much food you feed them and how often
3) How often you remove the waste and pollutants.
Now change the closed environment to a fish aquarium and the people to fish. Principle stays the same. If you understand those three, you'll be successful.
The standard they usually say, is you should not go over 1" of fish for every 1 gallon of water in a tank. Most pet stores have the adult size listed on the side of the tank. Go by that number. Don't go over our formula! The problem occurs when people want to shove more "people/fish" into that closed "room/tank".
When you feed your fish, you want to keep in mind that their little stomachs are the size of their eyes. Their tummies fill up fast. Instead of one big meal that they will not eat, give them two small meals a day - breakfast and dinner. Once the food hits the ground, they won't eat it - no 5 second rule. It just sits and rots and pollutes the air/water and takes up the oxygen in the water.
At 1" of fish for every 1 gallon of water, I change out my water every two weeks. I have stretched it out to every three weeks, but the air/water is tainted with rotted food and waste. The best would be every week, but I am lazy. Every two weeks works. If you have fewer inches of fish per gallon, you can go longer between water changes.

Clean Water; Happy Fish © etva
The more frequently you change your water, the less polluted water you have to change. The longer between intervals, the more polluted water you will have to remove to make a difference. Our water change rule is rule is you never remove more than 50% of the water, the least is 10% to 15% - you'll vary somewhere between, depending on all of the factors above.
Don't get any fish yet! We need to discuss temperature of the water and the type of fish to get next - Part 2.
Part 2 can be found here.
