Do I need to start from scratch

[Butterflydiscus2500]

Hi guys, I have a fish tank that had fish in it about 4-5 months ago.
The filter has been turned off for a few months and I’ve just been cleaning the tank every now and then. The tank have live plants in it which are doing well. I’d love to get it all going again and add a new filter in (that’s better than the original filter that came with the tank) and get some fish in there. Can I have some advice on where to start? I’m thinking of popping some neon tetras and a couple of Pygmy Cory’s in. It’s only a 2 foot tank

 

[StripySnailGirl04]

First of all, before deciding anything to stock the tank with, you need to know your water hardness in pH, GH and KH.
Neon tetras need a minimum of 20 gallons.

 

[JuiceBox52]

Agree, we need the above info, and the complete dimensions, depth, height and width.

 

[Butterflydiscus2500]

No worries I’ll get that - but say once I’ve got that all on track am I good to go?

First of all, before deciding anything to stock the tank with, you need to know your water hardness in pH, GH and KH.
Neon tetras need a minimum of 20 gallons

 

[Naughts]

The tank will have lost a lot of beneficial bacteria and if you replace the filter you lose more so there could be problems with ammonia once you add fish. I recommend keeping the old filter for a couple of months after the first fish are added. You would need a test kit to be checking daily that ammonia and nitrite are at zero.
Once everything on the tests has been stable for a few weeks you could add the new filter but then don't remove the old one for another two months.

 

[TNG]

No worries I’ll get that - but say once I’ve got that all on track am I good to go?

Your tank may not be fully cycled given that there were no fish in it for quite a while, although it shouldn't take long to get it to fully cycled again as all your plants are there.

If I were you, I'd do a fish in cycle, a few fish at a time.

 

[StripySnailGirl04]

No worries I’ll get that - but say once I’ve got that all on track am I good to go?

If it is cycled, yes.
If no, don't rush.

 

[Rocky998]

I would be doing a fishless cycle. We do not know how ready it really is for fish at this point. You may have a little beneficial bacteria but with the filter not running for 4-5 months and there have also being no fish during that duration, most of the beneficial bacteria may have gone away. So I think the most responsible thing to do is do a fishless cycle to avoid any unneeded stress or fish deaths
Make sure they you have a test kit. (Preferably a liquid drop test like the API freshwater master kit)

 

[Naughts]

I would be doing a fishless cycle. We do not know how ready it really is for fish at this point. You may have a little beneficial bacteria but with the filter not running for 4-5 months and there have also being no fish during that duration, most of the beneficial bacteria may have gone away. So I think the most responsible thing to do is do a fishless cycle to avoid any unneeded stress or fish deaths
Make sure they you have a test kit. (Preferably a liquid drop test like the API freshwater master kit)

You are correct but the filter has been wet so might have beneficial bacteria AND "live plants doing well" tips the balance to a planted cycle IMO.
Obviously a test kit, monitoring and water changes if/when required are essential.

 

[Naughts]

ButterflyDiscus, could you post a photo of the tank so we can get an idea of the plants?

 

[Rocky998]

You are correct but the filter has been wet so might have beneficial bacteria AND "live plants doing well" tips the balance to a planted cycle IMO.
Obviously a test kit, monitoring and water changes if/when required are essential.

The beneficial bacteria can go dormant BUT in 4-5 months with barely any nutrients I suspect a lot of them have died off...

 

[Byron]

I am on a different tact here. First, if the filter was "shut off" for several months, discard the media and buy new. You can use foam/sponge alone if you want, as you have plants. Any nitrifying bacteria in the filter media is likely dead now, because it has been so long and the plants will have gobbled up any ammonia faster.

Plants...can you post a photo of the tank so we can see the plants (species and numbers). There may be no need to fuss over so-called "cycling," but we need to see the plant load.

You mention cories...these need a soft sand substrate. And we need to know the GH and pH of the source water.

 

[TwoTankAmin]

Get an AquaClear, uses sponges. If you have lots pof plants, do not bother with a cycle. You just add fish gradually and be fine. There are still some nitrifying bacteria in your tank if the plants are doing fine.

However, as to what fish you need to listen to the above posts about your water parems. One note here. A tank with no real surface agitation and no regualr water changes may have different water paraneters than a running stoced tank. So you should also test tour tap water as well as the tank water.

The way to test ones tap is either to bubble an airstone in a container of tap water or else to let it sit out over night before testing. If you do not have test kits for GH and KH and have a local fish or pet store that sells fish, they might test GH and KH for you if you bring a sample (after it has been left out overnight). If they ask, tell them you need this info for the people who are helping you to pick the best fish for your tank.

 

[GaryE]

I would get the new filter running. I would add slowly, maybe 3 fish a week until you are at the stocking you want. Slow but steady wins the race.
I would safely assume the plants will harbour enough life to kick start things, but you don't want to overwhelm the cycle in place. The filter will be colonized slowly and steadily. You can test kit the process if you wish, but it will be happening. You make sure you don't miss water changes (30% weekly) and as long as you've bought healthy fish, they'll be fine.