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Algae problem

June 27th, 2006, 11:40 AM
Hi everyone,
I am now the proud new owner of 10 goldfish (feeder fish, I am told) their new home is an outside water feature.
My problem is the algae is starting to build up. How do I get rid of it? Is there something I can buy to put in the water, that won't harm the fish? Or do I have to buy an alogae eater??
Any help would be greatly appreciated

June 27th, 2006, 05:25 PM
Hi there,
this is a pond I guess you mean by saying water feature lol
Depends really on a few big the pond is for one.
Feeder Goldfish are common goldfish, they common reach 18 inches
to 3 feet long, depending on the genetics of them...some are badly
inbred and infested with many diseases, so may not grow very large
or live very long.
The algae build up youre seeing could be caused by several factors.
First, location....does the pond receive full sun at any point in the day?
If so, your solution could be to grow some bushy overhanging trees
to block the sunlight. Filtered light is best for ponds to avoid algae growth.
Second, feeding the fish. Large amounts of fish food, can deteriorate in the water, causing nitrAtes to rise. A lack of plants in the pond, espescially if its new and plants are small, leave nothing to eat up the NitrAtes. Because of this lack, nitrAtes rise and rise, and Algae grows to consume it. Your solution, feed the fish once a day, 2-3 pellets each, ensure all is eaten and remove any uneated food with a net. Add more live plants, or play the waiting game till the plants grow enough to combat this.

There are some other ways you can combat Algae. An algae eater you could do....However...depending on where you live, what the temperature gets to in the winter, whether or not you are going to heat your pond in winter to prevent freezing, all contribute to whether or not you can get an algae eater.
There are several types which will flourish in cold water, those of the Chaestotoma species, the Rubbernose Plecos. These guys come from high in the Andes mountains, and will tolerate water temps in winter in the 50' long as it doesnt freeze over, and as long as their is water movement and aeration, via a pump, filter, or fountain. These plecos also, do not grow very large, the largest of them reaching about 8 inches, with many varieties staying between 4 and 6 inches. You would want to allow 30 G of pond space PER Individual Rubbernose Pleco. Any less will cramp them and not provide enough food. You also will need to drop a few Wardley Shrimp pellets into the bottom of the pond after dark once or twice a week to supplement their diets. They are herbivores, but they do need some meaty foods. You also should place at least one medium size peice of wood in the bottom, maybe in a dark shady corner weighted down, to provide something for the plecos to get roughage from, and hide on. The will eat wood for fibre.

Most other plecos are tropical fish, and therefore will not survive in most ponds in the winters. Most of them require temps above 65F to survive, any lower will severely compromise their immune systems and digestive systems.
Also, many of them, like the Common Pleco, grow to 2-3 feet in length, and at that size, wont resist a munch on a goldfish now and then. I would avoid them.

There are also Pond Snails, small snails that feed on algae and rotting plant debris, are harmless to plants and fish, but will reproduce, sometimes to
insane numbers, depending on the amount of food available. The more food, the more snails you will have. If you like snails though, and are willing to squash a few now and then when number become larger, this could be the way to go. It wont completely rid you of algae, but will keep the algae population in check.

Now, there is 2 non-fish ways to combat algae. Barley straw.
Add 1 leaf (off a bale) of Barley straw, tied to a rock and weighted down to the bottom, per 20 G of pond water. So if you had a 100g pond, youd use 5 leafs off a bale, or about 1/6 of the bale. As the barley straw starts to disintegrate in the water, it releases an enzyme that kills free floating and sedentary algae. Replace the barley straw every 2-3 months.
Another way, which is much more expensive, is the Indian Almond Leaf.
1 Leaf will treat 50g. The water will take on a slightly tea colored appearance, will become slightly more acidic, and will also release an enzyme that kills algae.
Both these are safe on fish and plants.
There are also chemical products ...however, I would avoid them, Many will kill your pond plants as quickly as the algae, and some can kill your fish.

I hope this helps you, and gives you some viable options.

June 27th, 2006, 08:36 PM
OMG you definitely have a wealth of knowledge!!:thumbs up

Thank you so much for taking the time to thoroughly answer my question, with so many options :)

As for my water feature, well it's actually a huge flower pot that my Dh turned into a fountain.
My MIL babysat for us last week and much to my surprise when I returned there were 10 goldfish in it.
I am totally amazed that all 10 are still alive and well, and seem to really be enjoying their new home.

Thanks again, and I will definitely try some of your suggestions;)