Emergency crisis fish died what to do now after tank swap

[Tpricey]

Hi my name is Tim and I am having a fish tank crisis,

One of my fish died and I don't know what to do, I have had them over a year no problems apart from white spot,

Breakdown of what I have done over the last 48 hrs

My tank had a leak 48 hrs ago so I bought a new tank yesterday and began to set it up using the water from my old tank to the new tank, I did not wash anything put all my old tank gravel and  ornaments in, and put my old tank filter in as well without washing it, topped up remaining water with my treatments as u do, today I found one of my fish died unknow as of yet why,
I think my tank is cycling I have added a photo of dead fish and my tank,

I am afraid of losing more fish so any help would be appreciated

Do I do 25 percent water change? Or just leave it? Or am I missing somthing

[TropicalFishForums]

[Tpricey]

Pictures

[kas]

Hi Tim. Sorry to hear you lost your fish. The best place to start is the water. What are your ammonia and nitrite readings?

[Tpricey]

Many thanks, I am unsure at the moment till 2moz as I have ran out and pets at home (only place near me) don't have any as I have already been there, and order a kit which should be in 2moz, but the dead fish looks like is has a burn on his head which I notice yesterday but he was happy last night, I'll post a pic in a min, one other fish looks abit iffy, oscar looks happy and my dj looks alright, just my rainbow looks abit stressed right out

[Tpricey]

Fish

[kas]

I would do a 50% water change now just in case.

[Tpricey]

Even tho I only filled it up yesterday ? Ok I right on that now leave the fish in there yeah?

[kas]

From your first post you suggested that you filled your new tank with the water from the existing leaking tank? When did you last do a water change, and apologies if I have misunderstood?

[Tpricey]

Yeah I use 70litres from my old tank and filled the rest up with fresh water gone from a 70l tank to 180l

[Tpricey]

Last water change in the small tank was 2 weeks ago and that was a 25%

[kas]

Understood. Difficult to say what might have happened without results of water test. I do a water change of 40% once a week.

[Stephen]

Sorry to hear of your fish loss.

Sounds like an ammonia/nitrite spike.
All the crap from the unwashed old gravel stirred up in the new tank.

What fish died? I can not tell which species from the photo.

Do you have a new filter for the bigger new tank?

Best wishes
Stephen

[Tpricey]

I did leave most of the crap in the tank tbh, was a Malawi fish got my old filter running and a new one that glued into the tank jewel pump 600, I was always told when moving to a new tank not to wash anything and the run filter along side the new one for at least a week or is this incorrect?

[Tpricey]

And the tank is now clearing

[Stephen]

I did leave most of the crap in the tank tbh, was a Malawi fish got my old filter running and a new one that glued into the tank jewel pump 600, I was always told when moving to a new tank not to wash anything and the run filter along side the new one for at least a week or is this incorrect?

I was always told when moving to a new tank not to wash anything and the run filter along side the new one for at least a week or is this incorrect?

This is kind of true but normally refers to the filter and filter media.
I would of washed all the crap out of the gravel though.
Kept as much old water as possible and dosed with Tetra Safe Start (TSS) to replenish the beneficial bacteria in the tank.

How have you hardened your water to keep Malawi cichlids?
I thought it was a cichlid in the photo but told myself that Tiverton water was too soft for Malawi cichlids.

Stephen