Algea in February

[Dorothy Amyotte]

One thing to remember is that as long as you pond has ice but isn't frozen solid, the water temperature will be between 0 - 4C, and the fish don't know care about the air temp. A second thing to remember is the temperature of water changes very slowly compared to air.
Fish like algea, it has lot's of oils, vitamins and carotenoids.

Thank you, wish I would have known about this site a couple of years ago. Learned lots this couple of days. Thanks again

 

[Dorothy Amyotte]

I will of course remind you that 5 koi in 600 gallons will soon be overstocked as they each grow over 12+ inches.

Yes I know! I gave one away last summer, she was 12 inches long and felt sorry for her. Found a great couple with a large pond out in the country where she can swim. Thanks

 

[Dorothy Amyotte]

Algae lol

Doesn't algae produce oxygen? It's good food apparently for my fish, they love it. Also I rather like the look of it, but not pea soup conditions, just on the edge of liner.

But mine looked like pea soup. I've had the Po d for 4+ years and never had this problem at all. And when I started it I was told to beware of algea that it isn't good because it will take over and kill the fish. But I've learned alot this past weekend from this site. Wish I would have found this site earlier. So thank you for answering my question.

 

[budgenator]

Two more things about algae is;

Firstly it generates oxygen in the day, but at night it uses oxygen which can stress the fish, especially on hot summer nights when the warm water can't hold as much oxygen.

Secondly it's growing because there are nutrients for it to grow on, such as phosphorus and nitrates, too many nitrates in the water aren't good for the fish either.

A lot of us have a bog with plants that consume the nitrates as they grow, others change 10% of their water every week and a few do both. This keeps the algae from getting too carried away for most of us.

 

[Dorothy Amyotte]

Two more things about algae is;

Firstly it generates oxygen in the day, but at night it uses oxygen which can stress the fish, especially on hot summer nights when the warm water can't hold as much oxygen.

Secondly it's growing because there are nutrients for it to grow on, such as phosphorus and nitrates, too many nitrates in the water aren't good for the fish either.

A lot of us have a bog with plants that consume the nitrates as they grow, others change 10% of their water every week and a few do both. This keeps the algae from getting too carried away for most of us.

See that's why I was worried, I've heard this before. Ok I will build a bog this spring. This is the first time that this happens to me but in the middle of winter.

 

[Meyer Jordan]

See that's why I was worried, I've heard this before. Ok I will build a bog this spring. This is the first time that this happens to me but in the middle of winter.

Before people start running around in panic, a few facts need to be presented.
Yes, algae does utilize Dissolved Oxygen as also do submerged aquatic plants. Typically this does not present any real danger as in the total Oxygen budget algae and submerged plants introduce considerably more Oxygen to the water column through photosynthesis than they require during nighttime respiration.......a lot more. Algae blooms are a natural Spring time occurrence in natural waterways. Rarely does a fish kill result. In fact, they are necessary to kick-start the aquatic food chain each Spring. If the Dissolved Oxygen level is maintained at between 80% - 100% saturation during daytime hours, it is highly unlikely that this level, under normal circumstances, would drop below 60% saturation or 5 ppm, which is considered the lower cut-off before respiratory stress is induced.
As to Nitrate levels, entirely too much is made of the danger Nitrate may present to fish health. The LC50 value of Nitrate for Carp (Koi) has been determined to be around 1000 ppm
(Effects of ammonia, nitrite and nitrate on hemoglobin content and oxygen consumption of freshwater fish, Cyprinus carpio (Linnaeus)
K.S. Tilak*, K. Veeraiah and J. Milton Prema Raju)
Nitrate level in even the most neglected pond would be nowhere near this level.

 

[EricV]

The LC50 value of Nitrate for Carp (Koi) has been determined to be around 1000 ppm

What is LC50? I'm familiar with LD50 (lethal dose 50) which is what will kill 50% of the population. Is it lethal concentration? (LD50 is used for radiation as I recall).

 

[Meyer Jordan]

What is LC50? I'm familiar with LD50 (lethal dose 50) which is what will kill 50% of the population. Is it lethal concentration? (LD50 is used for radiation as I recall).

Very similar. Dose refers to a specific amount. Concentration refers to solution level at a 4 hour exposure.