noob needs winter help

thereds · 16-11-2011, 06:00 PM

Hi All,

I am new to keeping koi (about 6mths now), I have a raised pond with a depth of around 5ft. I have already vac out the bottom of my pond and have been using bio clean for a while now. I have cleaned out both the filters I am running but now turned off the uv lamps(end oct), but I am planning to leave both pumps and filters running throughout the winter. I have lagged both my filters using water tank jackets and I also brought a small 150w heater (just to keep a hole in ice if needed). I also have a tarp with reflective coating on one side which i was planning on covering over three quarters of the pond (this will be suspended over a wooden frame with about a ft gap to the water). my water temperature at present is low:8 deg (only going by forecast not measuring temp at night) high:11 deg (measured with digital probe at bottom, been around this for about 1wk now). I have been feeding nishikoi wheatgerm pellets in small amounts about 3 times a wk, my fish are still very active and are always swimming around looking for food. I know i have waffled on a bit(sorry), but I love my koi so much and want them all to get through the winter ok so if anyone can give me advice as to what temp I should cover them up or anything else which would be of benefit to me and my fish then I would be very very grateful thanks

miles41 · 16-11-2011, 07:11 PM

Hi & welcome to the site!

I can understand your enthusiam for your love of your koi and wanting the best for them - as we all do!
It sounds like you have a good set up with some healthy sounding koi

As the winter progresses you'll find the fish will feed less & less, and will stop all together when it gets too cold. This is normal. (I'm assuming the water is not heated)
The koi will survive without food through the winter and they will generally rest towards the bottom of the pond.
At 5ft depth that will provide them with enough 'shelter' even if you don't cover.
I didn't cover mine last winter and it froze over apart from the water return area, when it was -14°c outside, and i'm happy to say, my koi came through it

But any cover or protection you can give will certainly help.
Keep all pumps and filtration running all the time, raise any airstones to a higher level; other than that, just keep an eye on them as you have done so far.

Doghouse Riley · 16-11-2011, 07:15 PM

Hi thereds and welcome to the board.

We could do with a bit more information about your set up, but you seem to be on the right track. Insulating your filters is a good idea. If your pool is 5ft below ground level it will absorb some heat from the surrounding earth.

My fish have pretty much stopped feeding now, in my unheated pool.

Your pond cover won't keep any heat in unless you stop the wind from getting in under the sides. The greatest heat loss is by latent heat exchange between the surface of the water and the passing air. I've a pool cover over 90% of my pool now, it just floats on top.
You might want to consider a net cover if there's many trees near you.

Davej · 16-11-2011, 10:27 PM

You are doing all the right things.

Its the wind chill that really hits the temps and any cover will be a big help.

Only other thoughts - Maintain filter cleaning over the winter and continue to change water regularly.

If the fish are active and want to take a few pellets then give them a few but dont overdo it.

One other thing, if you are in a soft water area then keep an eye on the pH.

Dave