Large Tank 90% Water Change Advice

[Mervin]

Hello fellow fish enthusiasts!
 
My 3.5 foot tank has been cycling for quite some time now, almost 3 months I think, it finished cycling a few weeks ago and I did a large 90-95 % water change as I was expecting to get fish the next day. I ended up not getting any and so added a little ammonia to keep the bacteria going. The next day I checked the ammonia readings and they hadn't dropped at all. Eventually they started going down but it has been taking about 3-4 days to get back to 0. Today and yesterday it has reached 0 in less than a day so I believe it has recycled again and I can do a large water change and add some fish.
 
I believe I made a mistake when I changed the water before, because it's a big tank it takes a long time to empty and fill up again, about an hour. During that time the decorations, heater, filter, bogwood and plants etc... were above the water line for quite some time. I think a lot of the bacteria must have dried out and died before I could get it topped up again. So my question is how should I go about changing a large tank when I have to do a large 90% water change? Should I remove the decorations and filter and place them in a bucket of tank water to keep the bacteria alive whilst I change the water? Is this where I went wrong?
 
Thanks for any advice in advance.

 

[snazy]

Don't worry about that. I've stopped the filters for way more than an hour without ruining the cycle. Maybe your readings were off because of the type of dechlorinator you used or something else caused the die off, but it's different in each scenario so it's hard to know what happened. But the bacteria and filter media shouldn't dry off in an hour time. Theoretically, when the filter bacteria gets shocked one way or another, it will quickly bounce back after 24hrs or so and will keep getting stronger afterwards.
 
But, regardless, as a possible solution, instead of doing a 90% water change at a time, do several smaller ones in a row. A bit more time consuming, but less stressful to the system I guess.

 

[az9]

you could get some biological aquarium supplement.