String Algae Problem

[twier]

I could use some help before I order two dump truck loads of black dirt!

16' by 11' by 3 1/2' deep 1 year old professionally built pond filled with 1" river rock
10' stream and water fall
upper and lower bogs
The bogs are 4' foot deep with a 18 inch L shaped colvert in them. River rock then fills in the rest of the bogs. Water is sucked in through the river rock from the deep end of the pond, pulled up through the culvert and pumped to the upper bog where it enters the culvert at the bottom of the L and flows to the top and out. The culverts are supposed to trap the sediment.
add bacteria weekly
25 goldfish
water tests perfect
lots of plants, lilies and water cabbage cover 40% of the surface
waterfall and big areator in the deep end and the areator does help significantly with algae in the deep end

To keep the algae somewhat under control I have to use algaecide and then vacum the dead stuff every week. Over an hour of work per week and it only looks so so and smells a bit. If I do not use the algaecide it gets very bad quickly.

My only idea to improve the situation is this. Because my mechanical filter does not actually remover anything from the pond I am thinking of adding some sort of skimmer/mechanical filter that you can remover and clean.

The album pictures are from last summer when it was brand new, no plants, no algae

Any comments or help would be greatly appreciated.

 

[DrDave]

Build a good bio filter like many of us have. Don't worry about string algae, although I wonder why you have it so late in the year.
http://drdaveskoi.tripod.com/html/doc_bio_filter.html

 

[koikeepr]

Unusual to see string algae this late, particularly where you live, but I've seen it happen. I also don't see you mentioning a filter...which should be your first priority. A good bio filter can help things here, and there will be no need to add bacteria (also expensive) every week. Do you have a filter?

If it were my pond I'd do to things aside from making sure I have a filter in there (which should be a given). Get a UV sterilizer light in there...your algae will disappear in a week with no need for any more expensive chemicals. Also, your 1" river rock is probably part of the problem, too, I would tell you to get it out of there...but I'm afraid you'd be backing the dirt truck up. No "pro" should build any pond--particularly one of that size--with rock in it. A clear liner bottom is all you need to keep things neat and clean.

I realize that people like the look of rock in the bottom of ponds because it "looks" or "feels" more natural, but cleaning all the muck that will end up in the bottom is just a complete headache.

If you could slowly remove the stones over time--even if you just did a bucket a week, you'd be better off.

However, that being said, if you do nothing else based on the fact that you're telling me that your water parameters are perfect-- if you hooked up a pond UV sterilizer--your algae issue will disappear pretty quickly. You simply install it in-line between your pump and your filter. You just cut and connect your flex hoses to it right inline. It's pretty easy and straight-forward.

I'm guessing on the volume of your pond based on the dimensions you've provided and I've calculated about 4,600 gallons. Based on that volume of water, most will tell you that a 55 watt UV sterilizer would be ideal. You could probably get away with one as small as 35 watts. They range in price dramatically, from very cheap to pricey depending on maker.

You really don't need to crazy here in my opinion, but I will tell you that the bulbs can be expensive. I buy a new one every spring on Ebay as part of opening up the pond, but I use mine 24/7 during the pond season. I have never had a drop of algae other than the normal 1/4" stuff that coats the bottom of the pond and is beneficial to the pond.

Some folks turn theirs on and off. In other words, if they see algae, they turn it on and when they don't, it's off. I've always heard opposing opinion on this in terms of bulb life. Some folks say you can then get 2 years out of your UV bulb doing this. Others say turning it on and off shortens the life of the bulb. I just prefer not to think about it and just always have mine on during the summer.

Here's an example of a cheap one on Ebay that is sort of a no-name brand, but should work fine if you're on a budget.

Here's a brand name Tetra one that is more expensive, but you're paying for a name/warranty, etc.

Of course, shop around. But if you're water parameters are good and you're doing everything else right--a UV light will take care of your issue lickety split. Some on the site will poo-poo the use of a UV and say it's unecessary. I won't have a pond without one. So, you need to decide what's right for your situation.

 

[twier]

Do you clean that bio filter out? Or is it just for ther bacteria to live in? My builder said the tons of 1" river rock would support all the bacteria I needed.

I could fill the upper bog's 4' vertical culvert with strapping tape or deer netting. That would be real easy.

 

[koikeepr]

Do you clean that bio filter out? Or is it just for ther bacteria to live in? My builder said the tons of 1" river rock would support all the bacteria I needed.

I could fill the upper bog's 4' vertical culvert with strapping tape or deer netting. That would be real easy.

then why are you adding bacteria each week?

Strapping would be an ideal place for bacteria to grow for sure. But still...that only provides for bacteria growth, which is great. Where is your mechanical filtration? Do you have pads or something to catch your muck that your pump is pulling in.

I can't believe your builder told you that 1" river rock in the bottom of a pond would be a good thing...I'm sorry he told you that. But that is not accurate.

 

[twier]

kiokeepr,

I thought the UV light was only good for killing floating algae? I only have string algae and it would not get sucked into the return pipe thus the lamp would never zap it??

 

[twier]

Kiokeepr,

I add bacteria weekly only because I think it will help. The only measure of suffient bacteria I know of is "is the algae growing fast"? Then you don't have enough bacteria.

I do not have any kind of filter media only the settling chamber in the bottom of the culverts. A filter that I can take out and clean is what I thought might be my next move. Any suggestions?

 

[koikeepr]

Ok, so Dr. Dave is 100% correct. You just do not have enough (or in this case) any filtration to keep the algae at bay. Again, that's something your "pro builder" did not do properly. Trust me, I'm not trying to bash you or your builder...am just trying to help you square things away and get 'em right.

If you have a UV light, it prevents any algae from growing. You would not have that string algae to begin with. So, you would need to remove it one final time and turn that UV light on. But if you don't have proper filtration all of this is a moot point, to the doc's point.

What does your your settling chamber look like? Can you take a photo or give us a drawing. Could you fit a large sponge or matala mat in there if you were able to cut/fit to size? I mean, settling chambers are usually a pre-filter to a filter, but I guess it would be better than nothing. Even something in your waterfall, perhaps that is mechanical.

Again, a photo of your mechanicals set up and your pond would be helpful to assist you.

 

[DrDave]

Everyone knows I am not a fan of UV. That said, almost everyone also says string algae cannot be prevented or managed by UV.
I say, manage the string algae by pulling out excess, the pond will eventually rid itself of it. Mine does every year and I never use anything but my hand to remove it.
The fish love and feed off of it. Mine like to play in it. Fry hide in it. String algae is not a bad thing if managed naturally.

 

[twier]

Boys I appreciate the help. I drew a picture of the mechanics.

 

[koikeepr]

I've never had algae of any kind and I attribute that to proper filtration and a UV. Of course, we agree to disagree.

My head might be foggy from too much wine tonight, twier, but I'm afraid I just don't understand your drawing. LOL!