Iz this tank cycling

[1 LARA]

So 3 weeks ago I got a new 25 gal.
I put pool filter sand in , properly cleaned.
It obviously has new filter.
I took water from my already cycled 75 gal and filled it up.
Put in 3 Platies, 2 Corry Cats, 2 Swordtails and a Silver Molly.
So far the silver Molly, a Corry Cat, and a Swordtail died.
1 of the Corrys is still alive azwith the Platies.
Today the tank looks a bit cloudy like if there was a cycle going on.
Here iz todayz parameters

pH 7.6
Ammonia 0
Nitrite .50
Nitrate about 40 - 80

Should I pwc or if it iz cycling, how long to wait for next pwc?

 

[smkooq]

Since you said you filled your new tank up with water from your cycled tank. It would be hard to reflect how far you are in your cycle in the new tank.

Assuming your cycled tank water had nitrates in I would think you are receiving the nitrates from the cycled tank water. (Dont confuse nitrate readings as having beneficial bacteria, nitrates are just the product of having the beneficial bacteria).

I would do large water changes and seed the new tank with the substrate or filter media from the cycled tank.

 

[librarygirl]

Water from a cycled tank contains virtually no beneficial bacteria. So the tank started cycling when the fish went in. The fish likely died from ammonia poisoning. Now you seem to have gotten through the ammonia phase but are in the nitrite phase. Nitrites are as toxic to fish as ammonia, so you need to get nitrates down under .25. I'd suggest a 70% water change ASAP. Your nitrates are way too high for fish as well and should come down (the pwc will help). From now on, test your water daily and any time nitrite goes over .25 do a water change to get them down. This may mean more than one water change per day; it's ok. Water changes will not stop the cycle and they'll help save the rest of your fish. If you haven't seen it there's a link in my signature called "new tank with fish." It'll guide you through.

Also if you can spare some filter media from your cycled tank that may help as well but only if you can spare it. If you do I'd test the other tank for a good week to make sure you don't have toxin spikes in that tank and do water changes as needed until the tank can settle.

 

[bruinsbro1997]

I agree with librarygirl's above post.

Take some established media, which will speed up the cycle, and then start doing PWC every day, if not twice a day.