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Switching Substrates, Concerned About Fish

924 Views 5 Replies 4 Participants Last post by  queijoman
I have a mix of gravel and original Flourite in my 55 gallon that I have been wanting to switch out for a long time. 15 years ago I started it with gravel and then about 10 years ago I took out half and mixed in half Flourite. Gravel and Flourite doesn't look good imo. I'm now planning to take it all out and put in Black Flourite. I would love to put in Aquasoil but I don't have anyplace to put my fish while the ammonia is leaching out. I'm nervous enough as it is about the stress this is going to put on my fish, chasing them down with a net when I'm used to them taking food from my hand. I have some apistos that I'm especially concerned about. I'll then have them all with the plants in a large plastic container with water from the tank while I empty out the old substrate and put in the new. And then transfer everything back. It seems easy enough but I'm wondering if anyone has any tips in making it as easy on my fish as possible and just ways to make the job go smoother. Will I go through a mini-cycle?
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I've done it the way you describe and not had any losses. There is certainly some stress to the fish, but if they're healthy, I would think they'd be fine. As far as a 'mini cycle', if you're heavily planted and you're re-using old hardscape, I wouldn't be concerned about it. Be sure to maintain the biological filter media properly during the switchover.
I would make sure the plastic container is big enough for the fish to not feel too crowded. You could maybe put a few pieces of rock or driftwood from the tank into the container while you change out the substrate so they feel a bit more "at home". But most importantly, cover the container and keep it dark. That will make the fish more docile and they might just sleep through the changeover. You should probably keep a heater in the container as well, and maybe an air stone or something to keep it oxygenated.

When I changed my dad's 55g from gravel to sand, I was going to do it your way, but instead I opted to just grave vac really thoroughly and then scooped it out, replacing with sand. I did half the tank at a time, and the fish never left the tank. They were pretty stressed out but within a day they were back to their old selves and looking active as ever.
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I would make sure the plastic container is big enough for the fish to not feel too crowded. You could maybe put a few pieces of rock or driftwood from the tank into the container while you change out the substrate so they feel a bit more "at home". But most importantly, cover the container and keep it dark. That will make the fish more docile and they might just sleep through the changeover. You should probably keep a heater in the container as well, and maybe an air stone or something to keep it oxygenated.

When I changed my dad's 55g from gravel to sand, I was going to do it your way, but instead I opted to just grave vac really thoroughly and then scooped it out, replacing with sand. I did half the tank at a time, and the fish never left the tank. They were pretty stressed out but within a day they were back to their old selves and looking active as ever.
Yeah, I've considered doing it that way but I worry about the ammonia skyrocketing without me knowing it and doing some damage. I guess if you gravel vac it real well, that shouldn't be much of a problem. Who knows? Maybe I won't be able to catch them and I'll be forced to do it that way.;)
Yea I think that's why I decided to do it that way, the fish were such a pain to catch. The good thing about the gravel vac method is you're sucking out most of the ammonia and toxins. And when you add more water to the tank afterwards it just dilutes any ammonia left in the tank.
I changed my large gravel nuggets with small gravel a week ago, and have had good results by vacuuming the gravel with about 10 gallons of my 29 gallon tank., taking out the old rock and putting in the new w/o ever removing my fish. Just in case, I left a cut-open milk jug full of my old gravel in case it would be necessary to keep it there to filter the water until the new gravel can get the beneficial bacteria. I still have it there but I plan on taking it out this saturday. My fish have been fine since the day after w/ no losses. I guess my strategy was to keep as much water the same as I could and also not bother the filter. I have been known to clean thoroughly it but not this time.
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