Did I just kill my fish?

  • We are currently upgrading MFK. thanks! -neo
I typically don't mess with filters the same time as water changes. I imagine that you changed water, the water was cold and dropped temps more than 2 or 3 degrees between that, the chlorine and then new unrinsed carbon probably was a perfect storm. I would test your water and observe the temps.

You are probably correct. I managed to screw a bunch of things up at once. lol
 
Not sure what mini cycling is, but with my limited knowledge and what I am picking up trolling on here, you are probably correct. I'm sure I stirred up some crap at the bottom of the tank which is just sitting there because the gravel is fairly new and there was no external filter with bacteria in it because I changed it. Plans for the future include an FX5 arriving today, no water changes at the same time as filter changing/cleaning, and only one side of the filter pad being changed at a time. That should keep things stable I would guess. It just pisses me off I killed two fish by not understanding all this.

You are in for more problems if you don't understand the basics of the nitrogen cycle. Water changes have nothing to do with it, when you pulled out a filter pads you removed some bio filtration and poisoned your fish with their own waste.
 
Welcome to MFK. Here are links to a few threads that will explain cycling and filtration setups a little better for you. I know it can be overwhelming at first, especially since there is no perfect setup for everyone, but with a little time, research, and experience then you'll have it down. One thing you need to go out and buy asap is a test kit. Most people here will tell you that you need a liquid kit, and I agree that they are better, but a strip kit right now is still better than nothing. You also need to get a water treatment like prime, all major fish stores carry it or an equivalent product, and it needs to be added every time you do a water change.

http://www.monsterfishkeepers.com/forums/showthread.php?88677-Beginners-Guide-to-Filter-Media
http://www.monsterfishkeepers.com/forums/showthread.php?94937-Aquarium-Filtration-101
http://www.monsterfishkeepers.com/forums/showthread.php?224559-Cycling-and-You
 
Got it, thanks for the help guys! I will read those tomorrow morning and hook up a test kit tomorrow too. Water looks great now, but I'm gonna test it before and after another water change just to see what's up. I'm not changing the filters for a while yet, and I'm gonna leave the rear mounted external filter on there even after I set up my new FX5.
 
That is why I'm asking questions now. What would you suggest I do differently next time?

What is your current filter setup and how long has it been running (not sure if this was mentioned earlier)? If we are talking a HOB I would not change any cartridge ever, just rinse in tank water once in a while. If we are talking a canister I would not bother with activated charcoal and replace it with bio media. Again never replace your media just rinse it out (never all at once) in used tank water. If you do need to change the filter media seed it with old media and do large water changes with prime and keep any eye on ammonia levels for the next week.
 
HOB filter only, and tank has been running a few months already. Man those links really made certain things a lot clearer, thanks for those. I'm understanding the nitrogen cycle now, and I would guess when I changed both filters and put new carbon in there I got rid of any bacteria that was managing the ammonia and nitrites in the tank. When I did the water change close to the bottom, it stirred up ammonia that wasn't being controlled by anything now. Next time I change that filter, I will reuse the old carbon media and put new carbon in as well. Actually this might be a moot topic soon anyways, as my FX5 will be here on Monday. I realize I will have to go through the same cycling time period with that filter, so that won't be too helpful until bacteria starts to build up in there and it can help control the ammonia build up in the tank. Actually after the FX5 gets dialed in, I can change the filter pads in the HOB without worrying nothing will be filtering the tank properly. Right? Thanks for the help everybody, I appreciate it.
 
There are many people here(myself included) that prefer to run two filters so you can clean one while you still have a backup that is fully seeded with BB. It wouldn't be a bad idea to keep using your HOB along with the FX5 for that reason, and just in case one of them would happen to quit working you'll be protected until you get it fixed.
 
That is my plan now. I really hate the HOB filter, but we are getting used to the noise already, and if I add the FX5, I'm sure it won't clog up as fast or get nasty nearly as quick. Still gonna get a test kit to see how all this works and where I'm at right now with each level. I'm guessing you don't want any level of ammonia or nitrite, and a reasonable level of nitrate (not sure what that level is), but what about pH level? Where does that fit in?
 
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