Clearing algae and silt loaded water

Like many people here our pond developed it's usual pea green algae
bloom this spring. On top of that the fish had been mostly unseen for
about 18 months after a plant emptied it's soil into the pond and turned
it murky.

So, after reading all the useful replies here, I decided to tackle the
problem. The methods that I chose were UV clarifier and filter wool.
The UV device is an 18 watt basic unit off of eBay, it cost about £45
with postage and packing. We plumbed the UV clarifying in between the
submerged pump and filter tank. The filter wool is 12mm thick, 1m wide
and came in a roll of 10m. We layered that two ply on top of the filter
media as a final filtration step before water exited into a small veggie
filter. Without the wool I don't think my Skipy style filter would have
caught the flocculated algae cells.

The result -
After one week the water was looking less murky, but still pea green.
After two weeks the water was 'transparent' but green.
After three weeks the water was crystal clear.

I suspect that the dissolved solids were rendering the UV clarifier
almost useless to begin with. Once the water was clear and 'transparent'
the UV could travel further and do more work on the algae.

The filter wool clogs up quickly, it will change from white to brown in
a few hours. We cut it in to squares that fit the filter tank and used
either 2 or 3 layers. They needed changing or cleaning every 4 or 5 days
while the algae was being removed. Now that the pond is clear they last
a week. It's wonderful being able to see the fish again, so I highly
recommend tackling the problem seriously to solve it in time for summer.

Thanks again for the r.p.m wisdom.

--
DavidM newsNO@_SPAMdjmorgan.org.uk
www.djmorgan.org.uk



DavidM

Congratulations, David!

Your post should be kept as an example of follow through with algae!
Now, lots of plants to continue grabbing nutrients and you will not
need the UV. You might try that out in a short while. We needed ours
at the start of the season for a number of years. This year, we have
not bothered as the water has been clear throughout.

Jim

Phyllis and Jim wrote, On 31/05/2008 01:39:
> Congratulations, David!
>
> Your post should be kept as an example of follow through with algae!
> Now, lots of plants to continue grabbing nutrients and you will not
> need the UV. You might try that out in a short while. We needed ours
> at the start of the season for a number of years. This year, we have
> not bothered as the water has been clear throughout.
>
> Jim

Thanks Jim. I think half the fun on ponding is overcoming these kind of
challenges, it gives a real sense of achievement. The trouble is, I'll
now find different things in the pond to focus on, that will probably
cause new problems

For the first few years our pond was crammed full of plants and the
algae was less of a pest. That seemed to introduced it's own problems
though, such as filters clogging up with partly decomposed plant and
trapped material rotting in the pond. I'm pretty sure that a bad fish
infection was due to organic pollution in the water. I removed most of
the plants a couple of years ago, and now try to keep them to their baskets.

Now that the algae has been removed, the small veggie filter is
overflowing with water cress and mint. The large iris in baskets are
also doing very well. Like you say, the aim is to turn off the UV soon
and hopefully let the plants starve out the algae. I expect it will take
a while to get the balance just right. Do you allow water to flow
through the until UV unit all year, or do you divert it. I'm not sure
how much damage will be done to the glass pipes inside.


--
DavidM newsNO@_SPAMdjmorgan.org.uk
www.djmorgan.org.uk

The water has been moving through the filter for a decade. No
problems. We do clean off the sleeve from time to time.

Jim

I am baffled, but after having NO algae with my "in pond veggie filter" this spring I
suddenly got algae. The temp had dropped again (outside and in the pond). I turned
on the UV and in 3 days it was clear. But I am surprised that the algae reappeared.
maybe because the pond was getting more sun. sigh. so my hope for not having to use
the UV are once again dampened. Ingrid

Bummer about the algae. I am hoping my pond does not hear about the
situation!

Jim

Phyllis and Jim wrote:
> The water has been moving through the filter for a decade. No
> problems. We do clean off the sleeve from time to time.
>
> Jim
>
Hi,

We have a fountain that is like a pond, in that it is 2ft deep and 10
feet in diameter. The problem I have is not only algae, but lots of
muck in the bottom. I don't raise fish or plants in the water. Last
year I emptied it and scrubbed it down. This year it was even worse
with leaves and debris on the bottom. The problem is since it is vinyl
lined with folds in the bottom, it is very hard to get the muck cleaned
out. Also we don't have a drain so I have to siphon the water out, so I
can't use water pressure to clean in the folds.

Does the filter you use fix that problem? If so, what kind of filter do
you use.

Thanks,
Sheila

Sheila wrote:
Last
> year I emptied it and scrubbed it down. This year it was even worse
> with leaves and debris on the bottom. The problem is since it is vinyl
> lined with folds in the bottom, it is very hard to get the muck cleaned
> out. Also we don't have a drain so I have to siphon the water out, so I
> can't use water pressure to clean in the folds.

>
The way I would attack this is
1) Siphon almost all the water out
2) With a hose, spray as much muck out of the corners and crannies as
you can.
3) Repeat 1) and 2) as necessary.

Chip

>Sheila wrote:
> Last year I emptied it and scrubbed it down. This year it was even worse
> with leaves and debris on the bottom. The problem is since it is vinyl
> lined with folds in the bottom, it is very hard to get the muck cleaned
> out. Also we don't have a drain so I have to siphon the water out, so I
> can't use water pressure to clean in the folds.

Hi Sheila, have you tried a shop vac after you've gotten it empty? ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

If your fountain has no living things in it, you can use an algecide
to keep it clear. You will still have to clean out the muck.

Jim