I shall impart my knowledge then. Some of them are more obvious to others, but I'll just type everything:
- Goldfish are cold water fish; Ideal being 68-72F or 20-22C
- They NEED a filter that can filter the entire volume 10 times in one hour. So if you have a 20 gallon tank, you need a filter that is rated for 200gph.
- They need either a large surface area (so a pond) or have an aerator to dissolve oxygen into the water. This is also why they are cold water fish, as cold water is capable of dissolving more oxygen than warm water
Their colours are similar to how people tan in the sun. If you leave them in the dark they will eventually turn into this pearly grey colour. Giving them some sun and proper lighting is important for activity levels and feeding.
They will destroy a lot of live plants either from eating them or uprooting so fake plants or very broad leafed plants (i.e. Anubias) are better.
-They are omnivorous so they eat plant matter and crustaceans/insects
-they are also like bettas; opportunistic eaters and will eat everything available
-you can tell that they are being overfed if you see the classic “poop dangling from their anus”
-Overfeeding them will cause their digestion to accelerate and cause more poop and ammonia to be produced because they DO NOT HAVE A STOMACH.
-Generally, none. Having an all-goldfish tank has a higher success
-Plecos and larger snails will eventually end up sucking slime coat off of your goldfish and cause it harm
-smaller snails are much better if you insist on having snails, but they may get eaten by larger goldfish
-unless they are at sexual maturity, it is very difficult to sex them.
-Males have thicker end rays on their pectoral fins (the ray closest to the front of the fish) and appear to be stiffer
-Males will also have “breeding stars” on the side of their gills which are little bumps. These bumps may also be present on their pectoral fins
I believe that answered most of the questions presented. The reason why they need a large tank is because they secrete both ammonia and stunting hormone which will dramatically reduce the quality of life of the goldfish. Considering the fish in question is a fancy/ryukin/fantail, I think 20-30 gallons with a high gph-rated filter should be fine. Keep the decorations to a minimum so he'll have room to swim. Bare bottom tank would be fine, too. While they appreciate some cover like most fish, they tend to get stuck sometimes. Use a testing kit to determine water changes :P
Last edited by bahamut285; 10-26-2011 at 02:30 PM.