Question about using old media to cycle a tank.

[FishyWarrior]

I was wondering, if i chose to use old filter media or gravel from a friend's established tank, how much would be enough? Like, is just a handful of gravel good enough, or would it have to completely cover the tank bottom? And how long would i typically have to wait before adding the fish in after?

 

[fishorama]

The filter media might be your best bet. It probably has more surface area than "some" gravel if it's a sponge, batting type pad +/or biobits (balls, cylinders). It's safe for your friend to share 1/4+ of the media (or if they run 2 filters maybe 1/2 from 1 filter). Is your friend's tank bigger than yours? That'd be good.

It's hard to say how many fish that might support without adding ammonia to say 1ppm & see how fast it & nitrite goes to 0. if in 24 hours, then your tank is cycled for a light but full tank's worth of fish.

Otherwise you can ballpark it a bit based on your friend's fish load, say up to 10 or 20% of their fishes' body mass. Not inches of fish; if they have big fish like a few angels or big gouramis, that might = 10 tetras or rasboras per big fish. So 5 angels = 10 smaller fish for you. Does that make sense?

You'll still have test daily & be ready to do big water changes to keep ammonia & nitrite under .25ppm...even that little can harm fish's gills long term.

Still, if your friend's tank is healthy it can really jump start the cycle. You'll have both nitrobacter & nitrosomes bacteria & they can multiply fast with ammonia (preferred) or fish.

So, remind us what fish you want & your tank size... & what are friend's fish & tank size? Will you add plants now? That can help too.

 

[Mr. Bones]

My method = I use nothing beside aquaclear filters and when starting a new tank the old sponges from a long time running tank goes in the new filter and the new sponges go in the old tank. Works for me..

 

[dougall]

I would likely use filter media, not gravel... just because of the size of the bacterial colony.

if you do that, use as much as you can. if you cannot transfer the media, just squeeze all the gunk and stuff out of it into your tank.

The bacteria colony will likely double each day or so, and if you feed sparingly, there will be less ammonia produced too.

but ultimately test your water to be sure, whatever you choose to do. and if there's enough bacteria being used to seed that will support the full fish load.. I'd likely add them all.

just feed sparingly, be ready to change water if necessary, and test as much as you can.. if you have 0 ammonia and nitrites with fish in the tank, you should be golden.

 

[FishyWarrior]

Thanks for the advice!

 

[FreshyFresh]

What size tank and what fish do you wish to keep? Like said, the purpose of using seeded media and/or décor is so you can stock right away. Before any of this, you should have an API master test kit on hand (or similar) to measure water parameters.

 

[dougall]

ND, ummm, only use media or gravel from somewhere trusted... Like a friend or trusted store.

There are other problems that could be introduced like this.

 

[FishyWarrior]

What size tank and what fish do you wish to keep? Like said, the purpose of using seeded media and/or décor is so you can stock right away. Before any of this, you should have an API master test kit on hand (or similar) to measure water parameters.

In the end i decided to add tetra safestart to my 40 gallon and cycle with 8 white clouds instead (the guy i thought could help i guess lives too far away and my other friend had a bought of ick before and doesn't want to risk giving me any of that) The tank was already running for nearly a week before i added them and all seems well, no signs of stress or illness, ammonia levels still really low. And today i'm going to be adding plants so if my research is correct, that should further help the ammonia levels and make the fishies more comfortable.

 

[FreshyFresh]

8 white clouds in a 40g is a nice light bio load provided you don't overfeed. A cycle should be slow and steady. 6-8weeks. I'd do a 50% weekly water change every week at a minimum.

 

[dougall]

Plants will help use ammonia (or nitrate or nitrite) if they are healthy and growing.

The faster the plant grows, the more it will use (and more of other nutrients too, including CO2 and light).

So, you might be better with lots of slower growing plants than a few faster growing. Or growing something terrestrial, but aquaponically in your filter would work well (Say Pothos)

But you should be fine, just keep watching your water parameters and change water where needed.