UV filter recommendations?

Now everything's warming up our pond has turned a beautiful shade of murky green. We've dug out specs, etc, and the pump and filters should be more than sufficient - but we don't really have any UV filtration (there is a small UV filter but its attached to the secondary filter and it doesn't get very much of the water through it - long story...)

So, we're figuring a UV filter that actually sees all the water would probably be a good idea, but there seems to be a large range of brands, models and prices on the market. Does anyone have any recommendations or suggestions? The one thing I'm concerned about is that a lot of them seem to introduce a lot of angles to the water flow - is this worth worrying about?

thanks

 

I`d starve it out of existance by diverting its food source to more useful plants.
You could use your existing pump depending on the type of filter you have, so no uv lamp and no extra power needed :wink:

 

Sorry, Hex - I'm having a bit of a slow afternoon :o. Please could you be a bit more explicit on what you mean?

 

Hi Tangle
The algae bloom is due to the increased nitrate production thanks to the warm spell. The algae takes advantage of the abundant food source and turns the water green.
If the nitrates are used up by something else the algae is left with nothing and you have clear water. Edible plants will happily make use of the nitrate to grow.
Depending on your filter, gravity or pressure type, you can utilise the existing pond pump so there`s no increase in power usage.

 

OK, I'm with you on the chemistry side, but I'm not so clear on the waterflow - are you suggesting sending the water through a filter bed planted with edibles (wouldn't it get very boggy?, how does the water get back in the pond - pond waterlevel is higher than ground level?) or adding floating edible plants (I can only think of watercress, and that brings the commercial watercress beds to mind - don't think the fish would be impressed!)? Or am I still missing the plot by a few miles :o?

 

Here`s a few pics of some chilli`s that i grew from seedling to fruit using this method to show what can be grown using the nitrate and other nutrients in the water.
I used the water from a 140L aquarium housing 4 fish, no soil or anything added to the water, just the fishfood for the fish. The main benefits for me apart from the chilli`s were no algae blooms, clear water, low nitrates and no water changes necessary..a regular chore for fishkeepers. It just needed an occasional top-up due to the transpiration of the plants.
Its as organic as the fishfood, but no pesticides or herbicides are allowed as they would kill the fish.





Your pond has more water so the nitrates may not be enough to support hungry chilli`s unless you have plenty of fish in there but it could easily manage lettuce and other leafy stuff.
Treat the pond as an extension to the soil garden instead of letting it go to waste :wink:

 

Hmmm. The problem I've got is space - the water level in the pond is raised above ground level, so the only area in which to put land-based leafy plants would be the top of the waterfall - but that's only about a square ft and its a reasonably large pond (would need to find the bit of paper to be sure, but from memory its well over 1,000L). I'm just struggling to see what hardy, fastgrowing leafy plants I could find that would make a significant difference given the volume of water - and what growing medium to put them in. I also have reservations as the pond already has duckweed in it - but that isn't rocketing away at the moment - I would have expected that to do quite a good job as a nitrate-sink.

Thinking maybe I should get the pond test kit out this weekend - at least that way I'll know whether there's a big nitrate problem or not

 

As the bacteria get going the nitrates will go up. The more nuisance stuff you have growing, the better it bodes for using heavier feeding plants.
The layout is perhaps the biggest factor and all ponds are different. If you have an area away from the pond that could work,a sunny fence perhaps. It doesnt have to be close the pond although its usually the easiest.
I guess the existing box? filter is probably somewhere up the waterfall with gravity draining it back to the pond?

If the edible plants are first in line to the goodies, the nuisance stuff is left with less and as the edible plants get bigger they`ll use pretty much all of the available nutrients. One tomato plant could strip the nutrient supply very quickly.

 

It would be tricky - "watefall" is perhaps a bit generous. The filters are such that the water outlets go straight into the feeder pool (the 1ft sq area, only an inch or two deep), which drains over a paving slab into the pond. Fall into the pond is only about 9 inches max. There isn't much space around the pond in terms of flower beds to adapt to be raised filter beds - and the garden isn't that big to accomodate them elsewhere. I'm wary of overloading the pump as well - trying to predict how the performance drops off with increased length of pipe, lift and complexity of plumbing is a nightmare!

 

Also meant to say that I know I'm probably coming over as very negative about this, but I'm just struggling to see how it could fit into my specific situation. I do appreciate the suggestions, though

 

With the space at a premium maybe half a dozen grass carp and the uv would be the better option.
I think the uv may have a uphill battle, the algae population will mirror the nitrate concentration.
Mother Nature doesnt let anything go to waste :wink:

 

I see what you're saying, but I guess I'm hoping that the combination of the biological filters (which should be more than adequate to control the nitrates generated by the fish and any plant matter that falls in), and a UV to floculate the algae so the filters can catch it would show a marked improvement over the current situtation.

Thanks for your suggestions . We could use more floating plants to give the fish some shelter, though, so that may well be something to start out with (even if they're not edible ones :wink: )

 

Get one of these Tangle,
http://cgi.ebay.co.uk/Fish-Mate-2500-Pressurised-UVC-Pond-Filter_W0QQitemZ370097125459QQcmdZViewItemQQptZUK_HomeGarden_Garden_PondsWaterFeatures_UK?hash=item370097125459&_trksid=p3911.c0.m14&_trkparms=72%3A1683|66%3A2|65%3A12|39%3A1|240%3A1318

 

My 2p worth

Not everyone has the room for a "veggie filter" For that's what it is, some grow cress in them, there are a variety of things you can grow.

A U.V. is a better option for most people and ideally should be installed on the flow to the filter side from the pump. Yes any bends in the pipework will slow the water flow rate down but so long as itâ??s not too slow this is good because it means the water is exposed to the U.V. tube for longer. One maker of U.Vs has a spiral incorporated so the water is exposed for the maximum time.

Plants on the water surface in my opinion are a waste of time, yes they do work*, but to be worthwhile you need you have almost all of the water surface covered, which to me defeats the object of having a pond. I would always suggest a U.V.

* Plants reduce the amount of sunlight hitting the water by covering the surface of the water.

 

I agree that most people haven`t the space but if they could use a gravel filled bed they can literally throw away the usual high tech pressure filters and uv kit. The gravel acts as the biological filter medium, it provides effective mechanical filtration, catching the solids which then break down directly where the plant roots can access them :wink:
A sponge type biological filter will eventually block up as they`re not great mechanical filters. The flow is compromised and the biological filtration suffers unless you clean it out.
None of the usual pressure or box type filters will remove nitrate, they are designed to create it :wink: