I am struggling with a Evil Baby Bio-Orb and ammonia. The following is my sad tale:

- Following a 3 day power outage at work (with no filter/circulation), the fish in my Orb (4 months established) all died. I am attempting to prepare the tank for re-population. These are the steps I have taken.
- Removed all dead fish
- Vacuumed dozens of times with 95%-75% water changes (over the course of 2 weeks) There is absolutely no deteriorating organic material left within the ceramic media
- Replaced filter but retained the old sponge and placed it in the new filter (I removed the virgin sponge)
- While replacing the filter, vacuumed thoroughly under the spot where crap accumulates under the filter
- Never removed the ceramic rocks nor added any "disinfecting solutions" (In hopes of retaining some biological filter) All new water is distilled and tested before adding to tank
- Increased aeration by adding a second pump and large airstone
- Added a mesh holder filled with Ammo-Chips (API)
- Test for ammonia and nitrites, nitrates daily
My problem is...despite having done all of this AND having zero (yes 0) fish in the tank...my ammonia levels are off the chart
- One time, I had a reading (with API liquid test kit for ammonia) of 0.25 ppm. I noticed some air bubbles within the filter and, as per the instructions, simply lifted the filter apparatus and tilted it to remove bubbles. I then reseated the filter correctly.
- Next ammonia check was off the chart despite having previously vacuumed all the organic debris that accumulates under the filter apparatus.
- In desperation ran a little experiment...Added a handful of the established ceramic media to a beaker of the new water to document any ammonia changes (considered the leaching out of ammonia or gremlins). Water in the beaker consistently reads 0-0.25 ppm
- Daily add Stress-Zyme+ (API) to the Orb as per manufacturers instructions.

Where in the world is all of this ammonia coming from, why does it not respond at all to large water changes and what the heck do I do now?

Can I ask first of all what coldwater fish you plan to keep in this Biorb?

I had several fancy guppies that seemed to be happy. My office temp remains steady. They were active, displaying, and without any outward problems. I would like to reintroduce guppies again.

Is this the 15 litre biorb? If so sadly it is not suitable for any fish regardless of whether the mysterious ammonia problem is sorted

As far as my experiment goes...the ceramic media that is sitting in a beaker with distilled water (and nothing else) is now showing an ammonia level of 0.5 ppm and is slowly rising. Are the rocks leaching ammonia into the water?

This may well be true. I am now aware that I will need to come up with a different tank. The ammonia is now a challenge to me, though, and I'd really like to figure it out.

Hi,

This is just a theory now so bear with me.

As you know, filters are populated by bacteria that break down fish waste to manageable nitrates. As those bacteria are living, when they die, they create waste and produce ammonia.

As the filter media in biorbs is the rock/substrate, the bacteria are dying off due to no fish waste to process, and this is where the increased ammonia is coming from.

Aside from that, 15L is way to small for any fish. Even my shrimp are kept at a minimum of 23L, and that requires a good bit of maintenance to keep water conditions good. I wouldn't risk the fish by putting any more in there, to be honest :(

Interesting theory. I no longer plan to restock it but the mystery ammonia is a challenge to me. I'd love to hear any other theories out there.