17 replies to this topic

[gavinharibo]

Hi.

My father has a pond and would like some information on keeping the water clean and clear.

He has not got any fish, but does have a filter.

Are there any chemicals that he could use to keep it clean.

Many thanks.

[BennyLava]

Clean the filter regularly and get an ultraviolet clarifier. They're about $80 and they will keep your water clear.

[PS3]

ultraviolet clarifier is your best friend i been useing the same one for 15 years
but not the same light though lol

[koikeepr]

Weekly partial water changes of 20%. It's the cheapest thing you can do.

Tell dad that your pond is like a toilet--with fish pooping, peeing in it and food debris. At least once a week, you need to "flush" the toilet by doing a water change to keep water fresh and clear.

[3qtkidz]

I really believe in a uv sterilizer - just make sure you get one large enough for your pond volume. Also, I have had luck with adding plants to my pond to cover about 40% of the surface. Surface plants helps to prevent algea from growing.
Good luck!

[lakesuperiorgirl]

Does a UV clarifier help with blanket algae? From what I am understanding, it only helps with suspended algae but if I am wrong, please correct me so I can go buy a new one as mine stopped working!

[koiguy1969]

u.vs are for single cell green water alge only lakesuperiorgirl .

[BennyLava]

lakesuperiorgirl said:

Does a UV clarifier help with blanket algae? From what I am understanding, it only helps with suspended algae but if I am wrong, please correct me so I can go buy a new one as mine stopped working!

Yeah it only helps with suspended algae. But that's what makes the water unclear, not the algae that is growing on the bottom and the sides. So if you just get a UV clarifier, you will notice a dramatic increase in water clarity in about 1 week.

In my personal opinion, you should leave the algae alone, that grows on things like the surfaces in the pond. It has benefits, but not really any drawbacks. If you are talking about a blanket of algae that grows across the top of the water, then you should just scoop that out with a net, and run your UV clarifier to help keep it from getting a foothold and coming back. However, koi are basically carp and they should feed on that algae. Perhaps if you just get one or two small goldfish or koi, they would eat it all.

[lakesuperiorgirl]

Thanks for the replies. What I am seeing that is annoying is on the bottom of the pond, covering the rocks, and once I sweep my net down there it is like hair. The other algae that is bright green and sways around in the water isn't as bad. I didn't know if it was worth messing with and whether or not a UV would take care of this. I have a Sunterra 2000 gallon pressurized filter that has the UV built in. It stopped working. I have a 4000 gal Sunterra pump located in my skimmer box that branches off to feed the filter and another line to the waterfall. My pond is about 600-700 gallon.

[DrDave]

This past week, both my ponds went from the worst string algae I have ever head to free of all string algae.
It happens every year. and those of you that have it will sopn find it goes away naturally. The 3 months a year I have it are always bad enough to clog pumps.

[koikeepr]

Have you ever tried using hydrogen peroxide to just kill it off?

[DrDave]

I dumped two bottles of it in about a month ago and saw no change. Maybe it was not enough for 1500 gallons. I was worried about the Koi, especially since it was spawning time.

[lakesuperiorgirl]

I sure hope I don't have to wait 3 months as that's about how long summer lasts here! How much peroxide would I use?

[koikeepr]

First, you try to remove as much of it as you can with a toilet bowl brush or some similar type tool. Then you buy the regular 3% solution sold in those brown bottles at the pharmacy.

The common figure you hear is 1 pint per 1,000 gallons of pond water. Pour right on top of the alagae--not the fish. You should see the algae start to turn white or brown within the next day. So get ready, because you do need to remove this dead stuff immediately as it can quickly clog everything in site. You need to clean your filter like crazy, too, until it's all gone.

The biggest potential problem is that if you have massive amounts of string algae you can create a very large oxygen demand so that's why physically removing as much as possible before doing this is critical. It may be necessary to have an aerator ready to put in the water. Adding hydrogen peroxide, while effective in removing algae, will essentially result in re-dissolving the nutrients which contributed to the algae growth to begin with. It's sort of a vicious circle sometimes.

I remember DoDad saying he used a 27% solution, but can't recall what his ratio was or his results. Hopefully he'll pipe up to recount his experience.

[lakesuperiorgirl]

Using 27% peroxide must be the kind used to bleach hair. I won't be using that strong but maybe someone else could use that info. I did put in a little aerator aquarium pump with a stone on the end and put it in the lowest part of the pond (about 3' deep) to help bring up some of the bottom layer of the water. I do have a venturi I built. I don't have koi just a couple of feeder gold fish. They made it through the winter but not the more expensive fish. Didn't find this out until after I bought the heater which unthawed a spot for the poor dead ones to surface to! I am thinking I need a better filter like a skippy. Problem is, I have my pump supplying a big rock that has a hole drilled through it so couldn't put the skippy there. Plus the pump also feeds the pressurized filter that feeds an old hand pump so couldn't put the skippy there either. Plants are beginning to fill in so that could help. Temps around here are really fluctuating so that is not helping. Thanks for all the good info regarding the use of the peroxide.