Not Long. These different species of fish need totally different water temperatures and so should never be kept together. The Algea eater is a tropical fish and should never go below 70F. The goldfish are cold water fish and should be kept at around 55F to 65F. Applying the basic rule of all aquarists " 1 inch of fish needs a minimum of 1 gallon of water " you will see that the tank is far too small to accomodate even one goldfish properly so the life span of the goldfish depends on how often you change their water and how good the filter is.
You could put in more goldfish. You could also try some White Cloud Mountain Minnows. If you want a Algae eater then you could get one or two Chinese Algae eaters.
It depends, if your goldfish are smaller than your algae eater, and big enough to fit in it's mouth, then very much so. If the goldfish are small, but too big to fit into your algae eater's mouth, then he might just injure them. But your algae eater shouldn't be so small that your goldfish could eat it. The rule with fish that I always go by is, if it can fit into it's mouth, it will be eaten.
Yes, but only for a very short time, for goldfish are known to grow rapidly.
Goldfish need plenty of room to swim around and get very large. In a 1000 gallon pond you could put 25-50 goldfish just keep in mind that goldfish grow very large and need about 20-30 gallons each when full grown.
You may want to add a liner to be on the safe side, but you could have 2 fancy goldfish, one one common or single tailed goldfish. (goldfish grow big and fast)
One inch of goldfish per gallon of water is often recommended, so you could keep around 7-8 small goldfish in a 30 gallon aquarium. Keep in mind that as goldfish grow, they will require more space, so fewer fish may be ideal for the long term. It's always best to research the specific type of goldfish you have to ensure they have enough space to thrive.
As long as they are not tropical. They like to eat algae and it is good if you have a lot of algae in your tank.
Wouldn't recommend putting a goldfish in a 5 gallon tank-regardless of what type or size of goldfish. This is because the goldfish would be stunted causing it to have an untimely death. The condition in which a goldfish is "stunted" is where the fish adjusts to its tiny environment so much as to stop growing. The fish will stop growing on the outside but will continue to grow on the inside. Goldfish are naturally messy and create a LOT of waste. This factor would cause the tanks water to be poluted which inturn could kill not only the goldfish but possible your mollies too :(. Two mollies is enough for a five gallon tank. If you truly want to get a goldfish you will have to house the goldfish in a 10-20 gallon tank with very good filtration
If it is man made then you could possibly remove and scrub it.
You could have a school of neon tetras (approx 6), or 1 fancy goldfish
Yes. It can seriously harm a goldfishes intestines if eaten and can cause fatal diseases to their brain or stomach if its fumes were inhaled. Green Algae is OK for fishes to be around but if excessive algae grows in tank then it could, too, be fatal.
Every Second! Gold Fish are Very messy and need a filter to keep them alive. I suggest you put your Goldfish in a pond. Make sure there is more than one, Goldfish have friends just like you and me. Or you could get a 20 gallon tank (the tank has to be big enough so goldfish can grow up to 10 inches long WITH a filter. okay long story short, one inch per fish needs at least a gallon!