We have a 30 gallon aquarium that is just awesome. Besides being very calming to watch the fish, it is also very beautiful. We have learned a lot about fish since our anniversary two years ago, when my husband and I found an aquarium and stocked it with some really cool fish.
We knew nothing about fish varieties as we were amateur enthusiasts (and I stress the word enthusiasts) and didn't know anything about cycling the tank and choosing the very best type of fish for our tank. Needless to say, some of our fish didn't make it. We finally had the water where it needed to be and our fish were healthy at that point. Our big mistake was letting someone talk us into getting mystery snails (their real name) to clean algae and waste in the tank. The snails were fine for a while and then they would turn this weird bubble gum color and in 1-2 days, they were dead. Our fish were starting to die again, little-by-little, so I decided to do some research.
Our snails had flukes, which we found out were using the snails as hosts. There are two types of flukes; the egg laying (oviparous) gill fluke and the live bearing (viviparous) body (or skin) fluke. Skin and gill flukes are caused by parasitic flatworms known as trematodes. They are called "flukes" because they have the same flattened body shape as a flounder (the old Saxon name for flounder was fluke). Skin flukes have been found to have more than 4 generations inside a single fluke. A healthy fish will be better equipped to withstand a small fluke attack, but a large fluke infestation can be very deadly. They can cause severe tissue damage and lesions and can be the reason behind hyperplasia of both skin and gill epithelium (Hyperplasia is increased cell production in a normal tissue or organ). When the skin and gills are damaged by the trematodes (flukes), it is even easier for new trematodes to attack the fish. Some symptoms of flukes are: sluggishness, flashing (rubbing against rocks or decorations and sometimes "bouncing"), reddened fins, drooping fins, fin damage, loss of appetite, isolation and there may also be excessive mucus production.
There are several methods of treating flukes, however, some medications are not effective in their treatment. Prazi is a great medication and is safe to use with even the most sensitive of fish; if it is used as directed, it almost guarantees elimination of the flukes (according to Pondr.com). Prazi doesn't affect your filter bacteria, which a lot of treatments do, and it lasts a long time. Prazi can be hard to find, but there are several online retailers that carry it including: Amazon, Rocky Mountain Discus Care Products, Doctors Foster and Smith, and Bonnie's Plants. This is not an inexpensive treatment; it is offered on Amazon for between $5 and $35.
We lost all of our fish, but we have learned a lot. We cleaned the tank and the gravel, decorative rocks, etc. with vinegar (works best, in my opinion to clean with and also is good to put on your hands and arms when having to place your hands inside the tank for whatever reason) just make sure to rinse well and when using on your hands/arms, rinse well and dry on paper towels to avoid transfer of any soap or laundry softener to the tank.
Make sure to cycle your tank; we use filtered water and a water conditioner (used to remove any chlorine, other chemicals, etc.), a good filter, an air strip with variable water pressure (to incorporate oxygen into the tank and also provide a current for your fish whose natural habitat is in a body of water with a current (whether strong or mild). It is good to add live plants to your tank, such as myriophyllum, varieties of water lily (lilies are good for fish that like a dimmer light in the tank) and crypt plants to help keep ammonia levels down and provide a nice hiding place for your fish also. We put beneficial bacteria in the tank (biozyme is the brand we used) to help cycle the water. You will get an initial "bloom" of bacteria that will turn the water a cloudy whitish hue; this is actually what it is supposed to do. You can add about 5 drops of a pure ammonia liquid (no scents, no added ingredients) to every 10 gallons get your ammonia level to .5, which helps kill the bad bacteria and algae. Cycle it for about 2 weeks and check the ammonia level to make sure it is appropriate for the fish and if all looks good, add about 2-4 fish initially and then another 4-6 in about 2 weeks (if getting tetras or other small varieties, you may add 6-8 because they are schooling fish and do better in a larger group).
We now have 12 cardinal tetras, 3 chinese algae eaters, 2 reticulated hillside loaches (they look like little manta rays and are so cool), 5 calico platies (we now have 4 little platie babies - awww!), 5 dwarf rainbows and a lot of brine shrimp that just appeared one day and are excellent for baby fish (fry) and fish who like live food. If you would like to find out more about fish diseases, symptoms and treatment, click here.
Good luck and make sure to do your homework; it will prove to be a lifesaver - literally!