During many years i built pond, join forums, i have seen many hobbyist do not have proper mechanical filtration. Many use "overstocked" japmat/other media which act as mechanical filtration. And have encounter many hobbyist ask for help for NPS, my pond water not clear, my water become green, etc.
NPS is a situation when nitrification cycle not mature. This will not totally responsible for your unclear water, green water, cloudy water. NPS is a period when nitrification bacteria cultured, and it only to remove ammonia and nitrite to nitrate. And this may cause fish sick, but this due to our false action as hobbyist. Many cannot wait to dump more fishes and start feeding, this may cause ammonia or nitrite boom which can bring fatalities to our kois. I will try to write about NPS in different thread.
You water condition happen to inadequate mechanical filtration plus feeding, and other debris that polute your pond. If your mechanical filtration is not good, this will pass your biological filter, and return to pond. Some maybe trap in your biomedia, but overtime it get more and more, and it usually happen 3 days to 1 week after you put your fish.
The common respond for above situation is WAIT, your pond is in NPS stage. But in my experience, if you put proper bacteria starter, you ammonia and nitrite should reach the safe point within 1 week at the most. And why the water not clear, some respond wait again another 2-3month, until you filter mature. And then YES, some reach the clear water stage after 2-3 months but many still fighting it, and begin asking WHY THIS HAPPEN???
The reason is, some have more biological media such as japmat, which is get clogged over time, the media void is getting smaller and smaller. More debris get trap and less pass to pump chamber and back to pond. Some with fewer media will never reach that stage because too few of media to trap the debris. More layers mean more faster your water clear up. Let's us check using clear glass, how much particles get though your mechanical chamber, bio chamber and water return to pond.
And how many times we hear that hobbyist clean their bio chamber, and water get cloudy, and all blame to biological media? The same reason actually happen like above, since we clean our media, all the void clear again, and debris pass to pond again, the cycle is coming back again. Bacteria attach very strong to media and not that easy to die, unless you clean it with chlorinated water or let it dry. Cleaning with pond water and put it back to filter will never kill you bacteria, as long as it still wet, it will survive.
This is not the only cause for cloudy water, but usually what always happen. Wrong water circulation and water flow also sometime responsible for cloudy water. The debris and pollutant is not transfer to filter as soon as possible but keep circulating in pond, and even 1% can cause trouble overtime.
Mechanical is the heart to closed circulation system, the cloudy water is accumulated of small particles and DOC. Try to use commercial product to clear water, this usually a coagulant, the bind small particles into bigger debris, and when you clean your filter, you will surprised to see how much it is.
Final word, CLEAN WATER IS NOT ALWAYS GOOD, BUT CLOUDY WATER IS DEFINITELY BAD.
article taken from Mr Harry Luhur - pond maker and expert
maaf ya kalau bahasa inggris... silakan di translate sendiri...
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