Bio film

coweyes298 · Oct 25, 2017

I suspect my QT has bio film issue. The QT has been running for 4 months. And this batch of fish went into QT I started to see cloudy water when dosing metro + kanaplex, also cloudy water when only dosing coppersafe. I removed the copper and do a large water change, along with cleaning the filter media (it's a hang on back filter with ceramic ring and seachem matrix). The only thing I didn't clean is the tank it self and also the guts of hob filter. After the cleaning and water change the cloudy water went away for several days and now it is slowly going back.

Does that mean the only way to get rid of this bio film issue is tearing down the QT and sterilize it? Does small UV working for curing this bio film issue? And how about cleaning the filter media? I put them inside the zip mesh bag, so last time I only rinsed them in new salt water and that's it. Should I toss the media away and start a new one? I have several ceramic ring and also sponge inside my DT (my DT is parasite free), but those media is inside my DT for almost a year... I am afraid by using those media from DT will also causing bio film issue.

Maritimer · Oct 25, 2017

You've almost certainly got a biofilm - just about every wet thing does. At four months, from what I understand, yours is beginning to be a threat to the action of meds you might want to add.

Most QT / medication tanks should be taken down between rounds of fish, and a round of fish shouldn't go much longer than it would take to fully fallow a display tank. That having been said ... I've had cloudy water in quite new QTs - the last two involved phytoplankton (green and rust-brown), which I think I imported from my display.

~Bruce

coweyes298 · Oct 27, 2017

So I took down the QT and did a total cleaning with vinegar. The tank was also cleaned with IPA and rinse with vinegar + water for at least 5 times. Use hair dryer to dry entire tank. Equipment has been vinegar cleaned and sun bath for entire afternoon.

I did reserved half of my filter media (seachem matrix) that I added to the hob a month ago. I put it in a bucket with lid that I use for collecting waste water from frag tank that do auto water change. I discarded another half of media (biomax ring). I am setting up the QT back again now and the fish were in temporary 20 gallon tank with airline bubble and heater.

I do plan to add another half of new seachem matrix later today. Do I need to dose DR. Tim bacteria in bottle again?

Maritimer · Oct 27, 2017

Need to? Maybe not. You've got some bacteria in your Matrix, and it will eventually seed to your other biomedia. Depending on your bioload though, you may very well _want_ to hit it with a dose of Dr. Tim's...

~Bruce