Why is the sea murky?

i have come downstairs this morning to find the water in my tropical fish tank is really murky. i did a partial water change last darkness, added stress coat and there seemed to be no problem. filter seems fine. fish dont appear bothered at the moment. any ideas?
I don`t know you just stirred up some of the algae sitting on the bottom or in plants when you added the water? whether this is true it should settle and go back to normal
could be bacteria outbreak,
silt, dust or other stuff that fell into tank
could be some waste that slipped out of filter.

Give it time. What filter are you useing? You enjoy multiple tanks?
how often do you change the powered floss? Try adding a product called PURAGIN. It is an AMAZING!! filter material that does an amazing work of clearing water. I had a tank next to nasty murky water that normally would of taken a week to settle, it be cleared up in one day. It is a mabye 15$ for a little pack so its not the cheapest but it is worth every penny. and it is reusable.

but more than possible it will settle naturally. if its not clear in 7 days consequently you have a problem. But try adding a microfilter, new floss or PURAGIN.
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