Change Substrate


New Member
Reaction score
Im sure this question has been asked 10,000 times...but...I am new to owning an aquarium. I bought a 45 gallon tank with some decorations, substrate, etc. from craigslist. Due to my lack of patience, I rushed to the petstore and bought tetras and mollies and got the tank running. ive had it going pretty well for 4 weeks now...and ive decided to change the substrate, wanting to switch to sand, and I can also set all my decorations and bury airlines. question is would it be acceptable to drain and save the avoid having to recycle it? and place my fish, only 9 little mollies and tetras and 1 little redtail shark in a seprate tank..possibly 10 gallon or so. and change out the rock to sand and redecorate?

I don't want to kill any fish or make it hard on them..but I want my tank to look better and more put together.



Well Known Member
Reaction score
More than 10 years
Saving the water isn't as much a concern as making sure your decor and filter remain wet in the process because the gravel you're removing has a lot of beneficial bacteria on it. Thus, it's important to keep the bacteria on the decor and in the filter alive during this process. You could leave fish in there, but it'll likely be messy and stirring up things.
I'd use that water to fill the spare tank so it's water the fish are used to and put the decor in there to keep until after you've switched substrates. If you're not going to run the filter while you do the switch, make sure the cartridge or media stays wet so no bacteria is lost. I also wouldn't scrub clean anything or clean the filter.
Toggle Sidebar

Top Bottom