Changing Substrate on an Existing Aquarium

just do a full system change... take out the fish and change to gravle to how you wanted..
then bring the tank back up to speed and add in the fishes....
and you can always add bacteria to help speed the substrate breakin period.

good thinking, it would've been the stress of a life time for the poor fish. exept if you take alll the fish out, that will be a difficult task to get to.
thanx!

just take out the decor.. and be smarter than the fishes..... i work at a fish store so i know how they think...



fishes escape routines:
-the wiggle bob juke
-the mad dart
-the sly and sneaky
-the corner hiders
-and the disappering act

Definitely change all the water, because the gravel in a well-established aquarium is full of... well, dirt, so you'll foul up the water if you don't clean it up. Put the fish in a bucket, (I just used the one I use for water changes), stick in a filter, and put a desk lamp over it (for me this provided adequate heating). When you are done with the change, pour in new water, but leave enough for the water in the bucket. Then put the fish, and the water, back into the tank. The downside is that the movement and change in water chemistry will cause stress for the fish. If you don't have any fish that are sensitive to aquarium salt, I suggest adding some (1 tablespoon per 5 gallons), and keeping this concentration for a few days as a form of stress relief. Also, if you have a HOB filter, turn it off - I recently changed my substrate from gravel to Eco Complete and ended up breaking my Bio-Wheel filter when a piece of Eco jammed the motor. You can also keep some of the old gravel (I just put it in a disposable plastic cup... you can also use a pair of pantyhose) because a lot of the bacteria is there. You can remove it after a week or so. But bottom line: be very careful.

i really wouldint light up the tub.. that would cause more stress than needed.... just keep it dark and do your change.... bring the new water up to temp and seed the new gravle with the old gravle... let it set up and do any final changes .. and then add your fish and keep the light off

If you have good mechanical and biological filtration just scoop the old out with a clean dust pan and put the new in. I just did that a week ago on 3 tanks and it worked perfectly. No cycling issues, no clarity issues, and no stress issues.


Just be sure to clean the mechanical filter after it catches what gets stirred up.

When I swapped out my old substrate (beach glass type stuff..terrible I know) to more natural gravel, it seemed pretty simple. I put the fish in my WC bucket with tank water (I didn't bother moving the filter - I was just quick about it) scooped all the old stuff out, did a heavy vaccuum, put a few scoops of gravel in a thin clean sock, put in the new rinsed gravel in. I left the sock with the old gravel in for a few days, and everything was honkydorey. No issues at all.