"Gunther" wrote in message
t...
Gosh, it seems like the fun never stops, eh?
This post started as a diary entry, and I decided it
might be useful to get the opinions of others here.

Last weekend, _two_ of my three tanks seemed to crash:
measurements showed ammonia in the 1.0 range, with zero
nitrites and minimal (but detectable) nitrates.
I surmise a complete bio crash. I'm searching for possible
causes, and wanted to share the observations and maybe get
a clue I'm overlooking.....
Here are my case notes thus far;

- these two tanks almost always get maintenance together,
and usually in the same order: 18g then 20g;
- by contrast, the 55g is maintained on a separate schedule,
and didn't crash;
- over that time frame ( 10-14 days ago) I was experiencing
a rash on both forearms -- probably shingles -- and was
treating the itch with various combos of Lanacane (which is
benzocaine + benzethonium Cl + a pot load of inactives),
a topical antihistamine (diphenhydramine HCl + Zinc Acetate),
and/or a topical hydrocortisone ointment.
- I tried to make sure to wash (and carefully rinse) my hands and
forearms each time, aware that I was carrying weird chemicals,
but was it effective? did I forget? Did I just happen to be
cleaner each time I did the 55g?
- same time frame: I started making my own eclipse filters for
BOTH these tanks (but not the 55) using polybat, some
blue floss, rubberbanded onto an empty eclipse filter frame;
- the purple and blue rubberbands (from vegetable bundles)
seem to stink like chemicals after being used on these
filters.... _don't_use_them_anymore_!;
- started using Amquel+ (also still have some regular Amquel
in use), but I suspect it's been in all three.

I guess what all that drivel means is there's only one factor
that's unique to those two tanks: the stinky rubberbands.
Does anyone have any info about this phenomenon?
The odor is sharp, vaguely familiar (acetone? some petroleum
byproduct?) and distinctly non-aquatic.
(I suspect there's a 50-50 chance I contaminated the tanks
with my drugged forearms, but I would suspect that would
only happen to the FIRST (18T) tank...repeatedly dipping
my arms into it should have diluted the stuff before I started
on the 2nd one, yes?)

Thanks,
Gunther

PS: jobless rate is still here in Silly Valley :-|
I'm probably moving, but have no idea how or where.....


Hey Gunther
FWIW we recently experienced a similar bio-crash following a (possibly
over-exuberant) cleaning (algae scrub) of our 20G gravel-less tank. I
suspect (in our case) reason for bio-bug die-off is that our biofilter is
more tentative now that tank is gravel-less & thus is more vulnerable to
mechanical (or chemical) removal of good bugs via scrubbing of glass,
filters, etc.

By that thinking: 0 substrate = less surface area = less biobugs = slower
recovery rate after any insult to biofilter. Thus in bare-bottom tanks: big
cleaning / WC / meds can affect the biobug colony in a big way.
Conjecture...not fact

Are all of your tanks gravel-less? or does your surviving 3rd, unaffected
tank per chance have more/different substrate?

Re; Amquel+:
Following our recent bio-crash & during subsequent re-cycle we used
Amquel+(plus) for the first time.
IME Amquel+ works differently (& perhaps better) than earlier products like
Amquel/Stresscoat/Etc...
It eliminates nitrite toxicity 100% (which is new, and GREAT) but with some
surprising results.

We measured high ammonia readings during the early part of the re-cycle ...
despite frequent, & large water changes.
Both single reagent Nessler & 2-reagent Salicylate AP Ammonia tests read
positive (bigtime) even after water changes, even after use of Amquel+,
although the product claims to remove harmful ammonia and claims to be true
to Salicylate Ammonia tests.
After 2 weeks ammonia finally disappeared and in 4th week nitrate finally
appeared, but never a sign of nitrite on AP test kit. Using Amquel+, zero
nitrites were measured throughout the cycle!

So Amquel+ apparently = 100% protection against harmful nitrites!!!
or else nitrites just do not read on AP test kit under Amquel+
Either way, the fish fared well through it all
In my previous experiences cycling with GF, it was the nitrites that hurt
the most, not the ammonia.
So these 2 fish strongly recommend Amquel+

~MattO