lesliew I have a pond that is about the same size as yours. I have a gravity filter that keeps my pond clear all year round. This filter is outside of the pond and it looks like a large utility tub. I have it sitting right next to my pond so I put a small fence in front of it to cover the front of it. This is how my system is set up: my water comes in from a garden size hose into a tube that is about 5 in diamiter ( I have a rock that holds the hose in place). The water then falls into the very bottom of the filter in comes up through a small grate,furnace filter, lava rock in bags, then roots of iris, water celery, anacharis, horn wort and out a 3 in tube that feeds back into the pond. I have a bottom drain that allows me to clean this filter out every spring. When I clean it in the spring I take out all the iris, chop them to pieces and give to any fellow ponder that will take them, hang on to a clump about 6 in in diamiter. throw away all water celery, it comes back anyway, replace lava rock. I buy the landscaping type just make sure you rinse them throughally before you put them in. Buy a new furnace filter at hd they are about 5.00 and worth every penny. The grate sits up about 4-5 in off the bottom so that allows all the fish poop and rotted stuff to settle in that area. When you go to clean out the filter you will want to save this sludge...it is black gold, my plants love it in the spring its like a energy drink for them. Once you put it back together you are done until next year. I do have to clean my pump about every 4-5 weeks but that is easy and takes about 10 min. I have pictures of my filter all taken apart that I can mail to you, they were not done on a dig camera, just let me know.

Kelly, As tigerdunes has stated it would be helpful to know the brand because they do things differently, but it does sound like a 1" filter and they usually just slide out to be replaced. I have run into occasions that when they put the return duct onto the furnace they screwed into the filter rack, which means the screw is caught in the filter. You really shouldn't have to dismantle anything to get a filter out. I would start by checking that, and if that's your problem you can just remove the misplaced screw.

I'm not a plumber, but I am an engineer. I've mostly worked in dirty water since school, but I did mostly clean water then. THMs are trihalomethanes, and they are a class of chemicals called disinfection byproducts. Basically, any chemical that's added to disinfect drinking water reacts with naturally-occurring organic matter in the water (think the dissolved remnants of stuff like leaves, algae) to yield tiny tiny concentrations of these chemicals. The main thing that affects how much THMs form is the time the water sits in the pipe and storage tanks between the plant and the point of use. The last I paid attention to it, we know that THMs in massive quantities are carcinogenic in the lab. The rules your utility follows are an attempt to extrapolate from what we know to protect the public against exposure to tiny amounts over a long time. FWIW, my recollection is that the prime exposure path is actually via steam inhaled in the shower. The good news is that a carbon filter is a great way to remove the residual disinfectant (chlorine or chloramines), THMs, and other organic chemicals (VOCs- volatile organic compounds). And it takes care of the main complaint that leads to getting a filter in the first place- that the water doesn't taste good. I'm not a big RO proponent for home use. Unless you have someone who's immunocompromised or have a lot of dissolved solids (due to softening or from being in a coastal area that has saltwater intrusion), I think it's overkill. And it's expensive, has expensive consumables, and wastes a lot of water to produce a little. There are always exceptions, but that's my general feeling. Your faucet should be fine if you get a carbon filter. The problem with RO is that it makes the water more likely to dissolve metals it comes in contact with. Water that's just carbon filtered is still buffered to prevent this. I don't think there's a problem with going generic. The issue with the proprietary systems is that they lock you into their replacement cartridges and those are usually at a premium. You can get housings and filters much more cheaply. One tradeoff that comes to mind is that the proprietary setups may have an easier arrangement to replace filters. Otherwise, you have to be a bit of a plumber yourself to put together the housings, valves, fittings, etc. The simplest setup would be a single filter. This is like what’s in most fridge and point of use filters. There are combination cartridges that remove lead, cysts (tiny pathogen eggs that are very hard to kill) and have carbon for chlorine, THMs, VOCs. A step up would be a multistage system that adds a sediment filter and maybe a second stage of carbon. This is what we have in the water coolers at my office, which run on tap water instead of jugs. As for the pool, the color problem after the tornadoes is a bit of a stumper. Probably not something that’s going to happen often. And I don’t know if a simple sediment filter would take care of it. Otherwise, there’s a whole ‘nother set of chemistry going on in your pool, and frankly I wouldn’t worry about filtering what you fill the pool with unless it looks bad. Not to mention that a carbon filter that sits around unused tends to have some of the stuff it’s collected re-dissolve into the water sitting there. Last but not least, how well any of this works is dependent on how good a job of maintenance you do. Timely filter replacement is critical. Either based on a conservative time schedule or testing the filtered water for chlorine breakthrough. A buddy who does water treatment for Coke’s bottlers reminded me lately that it’s also a good idea to flush the system with unfiltered tap water when you replace filters. This puts some chlorinated water through so that you kill anything that’s grown in the housing and tube/pipes. Not something I logistically can do with my fridge filter but a very good idea. McMaster Carr (industrial supply house) has always been a good reference to get an idea of cost, but Amazon also seems to carry most everything these days too. I’d look there and look at some of the pre-built systems to decide what works best for you.

Here is an article covering the three types of pool filters you mentioned. It might provide you with a bit more information. I personally have a sand filter and have had 0 problems with it and found it pretty easy to maintain. I'm not sure on what kind of long-term costs you might be looking at with each. I believe sand is probably on the cheaper end to maintain (lats long and replacement costs are only around $100 for new media?). Why were you originally going with a cartridge filter?