I have a 6000 gallon pond with a 600 gallon pond running into it via two streams and waterfalls. My goal is to turn the top 600 gallon pond into a large DIY bio filter. I started to turn some pipe on a lathe to make my own media. It seemed to take too long, although I liked the quality of it. 5 hours gave me a garbage bag full. I think I will cut the remainder (100 feet of pipe) into 1 inch pieces and do a layer of each media. I have a large 1/2 horse air blower I can hook up to the inlet pipe to stir things up for those o so fun cleaning times. This was all before I thought of using the crumb rubber. I haven't seen too many listings other than the wastewater filter article. Thanks by the way, and one that tells of them using used tires for artificial reefs. I really want to try it, seeing i have access to crumb rubber, but I don't want to sacrifice my koi on a project gone wrong if you know what i mean. I am going to gather a bit more info. so if any one has any please let me know.

Check your 'in' tube. I have been having issues with string algae building up right where the water should be entering the bio filter. I have been taking care to clean that area every week when I change my filters. You may be getting good flow for a brief time, as you turn off the pump. If there is a buildup it may dislodge itself when the pressure of the water pushing on it stops. Then when the water flow begins again, it plugs up. Good luck.

Not really enough info to know...but in general the bubbles are caused by very small particles which act like soap. Scooping out the foam removes some of the particles because some of the particles are in the foam, they form the foam. But just like soap removing the foam only reduces the material. Whether the stuff effects fish and how long it lasts depends on what the stuff is, which can't be known. The assumption has to be it was from something in the filter. I often rant against these types of filters and these kinds of sellers for many reasons. In this case the seller wants the cash and tells you to wait out the foam. And he may be right. The foam will likely go away at some point. Maybe it out gases into the air, maybe it reacts with stuff in the water, maybe it breaks down into other elements in the water. Who knows? Sure doesn't sound like the seller knows or cares what the stuff is. He's gambling your fish won't be killed, which is a pretty good bet. The question I have for these type of sellers is...How can you sell such a piece of crap? What right do you have to gamble with my fish? It's a bio filter. It's suppose to reduce waste, not add it. Is that what you paid for? I don't like being scammed and would return the filter and vow never to return to that seller. The second thing is a bio filter has nothing to do with making water clear. Bio filters convert ammonia and nitrite, that's it. A UV filter clears green water. So maybe this filter has a UV too? That would fit clearing green water in 3-5 days. But that requires a proper flow thru the UV and 1600 GPH sounds way too fast for a 250 gal pond. But that depends on different things. You don't say how many koi you have or whether you're testing ammonia...but just as a heads up...green water algae consumes ammonia directly meaning it acts as a bio filter. A very good bio filter. If you have a UV this algae may soon be dead, actually probably already are dead (takes a few days for them to decompose and then water clears). If all this is the case you may see a jump in ammonia in the next few days depending on number of fish and amount of food fed. You want want to consider testing ammonia. My standard rant... I don't know what kind of bio filter this is but I'm betting static submerged media (pads, balls, whatever stuff that's under water and doesn't move)? These filters are very poor bio filters. I consider them worthless. That's just my opinion of course but I can tell you this, there isn't a single serious koi owner, koi breeder or fish farmer in the world using this type of bio filter. At least not for the last 15 years or so. That's because much better bio filters were developed in the last 15 years. Trickle Towers, Moving Bed, Bakki Shower filters have been tested (years ago) and found to be at least 30 times better at removing ammonia than static submerged media. These static submerged media filters are very cheap to make and are only sold to newbies. And I think that makes sellers of these very dishonest. But that's just me.

Algae spores are carried by wind, bugs, birds, etc. and so you will get algae in the new pond no matter what you do. If your filters are dirty, by all means clean them out and move them to the new pond. Use the old pond water so as to avoid killing the beneficial bacteria. If possible, keep some of the old filter media in some non-stagnant water to ensure you keep a lot of the good bacteria alive and then move to new pond when pumps are running.