The UV you mentioned purchasing in July will eliminate suspended algae if it's used properly and has the correct size lamp for your pond volume. Perhaps you can give some additional information about it. Particularly the brand and wattage of the lamp.

As algae dies, it turns into clumps of brown crud that will clog filters. The batting should help collect it. Filters may need to be cleaned daily until it's all collected.

There is no wattage listed for the UV light that came built in with my Smart Pond pump. I could smack myself for that! I do have access to another UV light, a 9 watt, that I had thought about hooking up to the smaller pump that I orginally purchased and running them both. What do you think? Anyway, I have been cleaning the batting around the pump and the black sponge in the pump when the water flow declines, which is about every other day. Today was the day. I had lots of green slime in both. I opened the top of the pressure filter and took a look at the fine and coarse foam pads in there and they didn't look bad at all, so I left them alone. I am at about 6 weeks in with the new set up. The water in my pond is a cloudy green. You can see about 3 to 4 inches down and thats about it. I read in the forum about a filter( I am assuming it is a type of pre-filter) that Horton makes with colanders and scrubbies. I thought I might do that. ( I hate washing that lava rock off, besides it is so darned heavy!) I also read on here that peroxide will kill the algae and have contemplated that, but that won't fix my original problem will it? Also, should I replace my fine and coarse filters in the "pressure filter" temporarily with batting also? I'm open to all suggestions. If Lowe's, Home Depot, or the local feed store doesn't have it, I'm pretty much out of luck as far as local resources.

You can replace the lava rock with scrubbies or wadded up nylon bird netting. They do the same thing with a lot less weight which is give the good bacteria a place to live.

Every time you scrub your liner and scrub your filter media you are going to upset the balance and prolong your agony.

Ponds are supposed to have algae coating the liner. A coating on plants can also be normal.

Neither waterlilies nor cattails are of much use for clearing up algae though waterlilies will shade the water some. You might get some underwater plants like anacharis, hornwort or cabomba they'll use some of those nutrients up. Water hyacinths and lettuce should too unless the fish have nibbled their roots which can happen.

A 9 watt UV lamp should eliminate the algae in a pond your size. Make sure the flow rate is not too high. A lower flow rate will expose the algae to more UV light. I would try a flow rate of about 300 gph. If that doesn't work, you may have to replace the bulb.

There are two types of filter systems needed in your pond. A bio-filter uses media like nylon or plastic to provide a place for healthy bacteria to grow. Bio material should not be cleaned. The bacteria helps clean your pond and reduces suspended algae. A mechanical filter uses filter material to trap particles floating in your pond. They collect fish and plant waste and should be cleaned often.

Using batting and other mechanical filter material will help clean your pond. If the filters get dirty fast, you need to clean them often. Additional filters will help.

The string algae can be removed with a scrubbing brush. Peroxide will help reduce string algae. I use a pint to treat my 1,000 gallon pond. You would cut that dosage in half. String algae won't cause any harm to your pond, but it is ugly and most pond owners try to get rid of it.

I think I would work on the suspended algae (green water) first. Get the UV working a proper flow rate and keep the mechanical filter material clean. Each time you clean your mechanical filters you are reducing the crud in your pond.

Adding peroxide will result in dead string algae which will also clog your filters.

The algae on the liner doesn't bother me, just the green water. I'm looking into getting some submerged plants, not knowing how good an idea that is for this time of year. Do I understand that basically I need to have two filters...a biological one and mechanical one? I thought that the foam part of my presurized filter was mechanical and the bioballs in it biological. If so,I'm not touching the pressurized filter again( making it bio?), atleast not until I have to shut the pond down for winter. I have only rinsed the foam filters in it twice, and I have not touched the bioballs. Or, am I getting confused over something simple?

BOS and JohnKr gave you precise, first class information, about filtering your pond water and I hope they don't mind me butting in at this point.

Your Question was,

"I thought that the foam part of my pressurized filter was mechanical and the bio-balls in it biological."

You are correct with that thought.
Clean the foam pad[s] and leave the bio-balls alone, as you have done.
Just clean the foam pad[s] more often to rid them of the trapped gunk.

You may have to do it everyday for a week or so, or until you see the amount of gunk, that is being trapped by the foam, on a daily basis, is not plugging it up.
"Horton"

OK, so I was on the right track after all. The foam filters on my pressurized filter are never very gunky...probably because the filter on my pump is always a slimy gunky mess, which is why I put it in the pot with the batting and lava rock. I have to clean it daily to every other day, as the water flow declines. This has been the routine now for the last month. I don't want to add chemicals if I don't have too. I have pets and wildlife who drink out of the pond as well as the pondlife to consider, and I just figure that chemicals are more of a bandaid for the situation. But, my patience is wearing thin. I could be wrong ( it wouldn't suprise me!) but I think the weather here in West Virginia has a lot to do with my water problems. It has been one of the wettest on record. I think I am getting quite a bit of run off from this rain, which is why I am now considering raising the liner on my pond and berming it as a barrier. Am I wrong on thinking this?? Also, if I can get my hands on some submerged plants, would it be to late in the season for them to survive the winter season? I went ahead and hooked up my 330 ghp pump, made my version of "Horton's" filter, added the other 9v UV, and sank it in the pond last night. My poor pond now looks like Frankenstein with all the tubes and cords running out of it!!!

clarabelle63, be careful about starving your pump of water with the batting/lava rock filter becoming overly plugged up.
In fact I would remove both filter materials from the in put side of your pump all together. Just use the basket to stop ant hard objects from entering the pumps in port and allow the foam padding in you filter to catch the gunk.

A plugged up pre-filter could case your pump to overheat and damage it or even worse, burn it out.

I think you are on the right wave length, when you say that you believe the run off from the surrounding soil is the main cause of the problem. Lifting the liner up to form a berm, should help correct that problem.

Try not to get too frustrated with it all, as it is a learning curve, for most of us, when we become involved in ponds and water gardens for the first time.
You are on the right track, it will all come together, you'll see.
"Horton"

First let me tell you that I know nothing about the tech side of ponds. I have had trouble for years with trying to get clean water, it has been a nightly cleaning progress until I purchased an exterior pump, with 3 foam filters, then this two was an every other night cleaning. Until I heard 2 years ago about a guy that made his own filter and he uses Walmart cheap batting from the sewing dept(large bag for 1.97). So I tried it. removed the 3 foam filters that were always clogged and took forever to clean (left the bio-balls) and put in a handful of the batting material. Now about every 4 or5 days whenever I notice that the waterfall has slowed. I open it up discard the dirty batting and put in clean batting. Clear water and so easy. I know that most will not agree with me, but for me this works.

I've debated about removing the foam filters in my pressure filter and replacing it with batting, but those filters haven't looked too bad yet. My pump filter, on the other hand looks pretty cruddy most of the time. I'm guessing that I am like most everyone else, working on a small to non-existant budget and expecting professional results. I have $10 in Hortons filter and am giving it and my other UV a go. I have had it running since friday evening and if my water is any clearer, it is only slightly so. AH,PATIENCE! I have so little of it!