why did my freshwater aquarium turn green?

Question

i cleaned my freshwater tank, and within one week it turned bright green. it only has 2 koi and one algae eater.

Answer 1

Yes, you have a free-floating form of algea, and you shouldn't rely on chemicals to remove it. This will give you a "quick fix", but it doesn't address the problem of how and why it's surviving in your tank.

Light is one of your controls, and you can turn off the aquarium lights for several days without harm to yor fish. Unless your lights emit ultraviolet, they aren't helping your fish produce vitamin D3 - you need natural sunlight without glass or plastic blocking the light to achieve this. Actual sunlight isn't a good idea as it will aslo cause algae growth, and it can cause the water in the tank to overheat (ever sit beside a sunny window?).

Nutrients are the other thing the algae needs. Koi need large tanks, even when small because of the amount of waste they produce - these should really be kept in ponds, because they have the potential to grow 3+ feet. Make sure that you aren't overfeeding them, because this also contributes to the nutrients present in the tank. And you should have your tapwater checked, if it's what you're using in the tank. Nitrates are possible, and phosphates may be added by the supplier as a way to prevent corrosion. Nitrates and phosphates are oth plant fertilizers. Water changes will help reduce nutrients, but only if additional nutrients are in the water supply. If they are, you may need to change to reverse osmosis water (available in grocery stores, or at self-serve stations at WalMart), or use a media pad to remove phosphate that you can cut and add to your filter - most pet/fish stores should carry these.

Answer 2

Yes, this is undoubtedly an algae bloom. The heaters don't cause the algae, but it is the sunlight. You need the heaters for your fish. It seems as if you haven't been doing weekly water changes. Perform 25% of a water change every week, and once or twice a month at minimum should you be scraping the walls of the tank to get rid of excess algae. A 10 gallon tank is too little space for a Pleco, but you can get a snail or two to help keep the algae under control. Make sure you aren't overstocking your tank. What kind of fish do you have? If you have Goldfish, then you should know that each Fancy Goldfish needs a tank of 20 gallons or more with a filtration system made for tanks twice the size. If you have live bearers such as mollies, guppies, platies, and so on, you should only have two in such a small tank. Anymore would be overstocked, even three would be pushing it. I suggest you do some more research before purchasing anymore fish.

Answer 3

algae bloom caused by too much light, food, oxygen or as is more likely your water supply is high in nitrates or you killed your filter by washing the medium under the tap, Ive no idea what size aquarium you have but would hope its 55/75 gallon with 2 koi messy eaters, and you've not mentioned what the algae eater is, I'm guessing at a plec. all messy and potentially large fish.

you need to test your water supply eliminate that first, if its not that do another 25pct water change every two days, cut down the light, reduce feeding, and turn off any air supply or turn the nozzle on your filter to point lower in the water disturbing the surface less.

this should clear it fairly quickly, obviously if its not the water supply you'll have to pin down exactly what you did that's caused the problem the answer is above but which one.

AJ

Answer 4

Algae bloom. This is normally caused by an abundance of two things: food and light. Fish need only 10 hours of light per day to produce vitamin D. More than that, you can start an algae bloom. If you are overfeeding the fish, that adds extra food to the tank as well.
One way of killing it off is to remove all sources of light for a couple of days: aquarium lights off and tossing a light blocking blanket over top to keep sunlight, direct or indirect, out. In addition, fast the fish for a couple of days.
The other question though...how big are the koi and what size tank are they in? Koi get pretty big and are usually too big for a home aquarium and are better kept in large ponds.

Answer 5

Your tank is infected by algae, blah blah blah but I guess no one has given you the specific form of algae type.

Your tank is probably having problems with floating algae, chlorella and Euglenoids.

Possible cause include excess nitrate, excess phosphate, direct sunlight on tank and insufficient nutrient competition by aquatic plants.

To immediately cure this problem, drop some algae control chemicals into the water.(Could be found in most large pet retail outlets.) Also add some chemicals which says ''makes water clearer'' (Either by clumping up fine bits of algae or making larger algae bits smaller for easier filtration, depending on filter type.)

To prevent this in future, add drops of ''phosphate eliminator chemicals'' and install a water clarifier into your filter outlet.

You may have to get a series of chemicals for this process but it would make your tank good as new.If you are not able to afford so many ''drugs'' at once, the natural way would be to shift your tank away from direct sunlight and rinse the substrate of your tank before refilling your tank with water.

Answer 6

Your problem is algae! How long do you leave the lights on in your tank? Is your tank in direct sunlight? Leave your tank light on 6 hours max. Do 25% vacuuming and water changes weekly. Change your filter media, it could also be your bio filter(sponge). Test your water for ammonia and nitrites! Good luck!

Answer 7

it could be your filtration , or the condition of the water are you using water conditioner like start right if not you can find it anywhere like wal-mart walgreens publix
another thing is how big of a tank do you have if it is small you might want tobuy some smaller cleaner fish like tetras or danios they are sold at most pet stores and are hardy
also koi are very messy fish
you could be overfeeding and the decaying food wuld increase algea growth and raise the amonia levels in your tank.
hope this helps

Answer 8

Does it get direct sunlight? If so, then it's algae. The algae eater should eat it over time, but you should get an algae liquid just to be safe.

~ZTM

Answer 9

You may have introduced algae in you last water change. Use a combination of an algaecide and a phosphate pillow to rid yourself of the algae (but do a large water change first).

Answer 10

Algae bloom!! Freshwater clams are great filters and will clean up that bloom in a couple days and prevent new ones.