BIO-Spira + Fish??

[AEIOU9]

Last week I had a two deaths in my newly set up QT and one theory tossed out by the staff at the LFS is that I had an insufficient population of bacteria in the tank & might have had a "mini-cycle" as my parameters were clear at the LFS too.

I originally filled my QT with water from the DT, which had been cycling for ~3-4 weeks. However, I only ran a sponge in the DT for less than 1 day which probably wasn't enough time to populate the media sufficiently.

Regardless, I did some research on bacterial supplements and BIO-Spira seems like it works reasonably well for people. So I added some BIO-Spira tonight and a few hours later I'm seeing some activity in the QT:

• Ammonia - 0.25
• Nitrite - 0.25
• Nitrate - 10

So here is my question, for this stuff to work do I need to have fish in there or can I keep it empty and just let the bacteria populate my sponges & ceramic rings while the water parameters smooth out? Also is it a safe assumption that once my parameters are clear I can consider a "first" resident for the QT?

 

[Tarawa]

you need something for the bacteria to eat. What I did a week before I got fish after my DT cycled was I bought a few sponge filter pads foo aquaclear HoB filters, and threw them into my sump, then added 100ml of ammonia to the DT every other day (was prolly extreme, and why I had ungodly nitrates =D) but the sponges were loaded, threw that into a HoB filter on my QT when I got my fish, and never had a ammonia/nitrite.

Now I keep 2 in the sump all the time for new QT setups and emergencies, and I garbage the one that was in the QT filter when I empty it.

the bio-spira will work the same way, they'll need something to consume, ammonia, or ghost feed it, etc.