Kodiak wrote:
Thank you for your post Mark.
Thanks for all the info Cichlidiot...

They were just a bit lethargic last night for a few hours,
before I did the 25% water. They never got
close to the gasping stage. Anyhow, turns out it may not
be so bad, my nitrite kit tops out at 3ppm (really sensitive), and
it seems the tester was a shade under that last night so i estimate Nitrite
to be 2-3ppm. After the 25% water the fish reacted very positively
and were all swimming around this morning and evening
and eating fine. I will stop the feeding for a few days as you mention.
I just finished the 50% water this evening, they are now moving around
even more.

This sounds good. They probably were suffering a bit from nitrite
poisoning and the lessening concentrations are helping. Try to keep at the
water changes until you get it below 1ppm though (or at least below 2ppm
if you can't get it any lower).

I'm using pickling salt (pure 100% salt no additives).
However I'm wondering about the dosage you recommend.
1 tablespoon per 50 gallons is 0.01%, isn't that too low?
I'm at the 1 tablespoon per 5gallons or 0.1% (10x the amount you recommend)
is that way over the limit? I read somewhere on the web that was fine for
RD's,
Goldfish can handle up to 0.3% with no issues, but i realized these fish
have
different needs. Anyhow with this latest 50% I'm at 0.05% (1
tablespoon/10gal) right now,
so I will leave it there until i hear from you again.

Well, I base this off some research I did which said the concentration of
chloride ions needed for helping nitrite poisoning is very low, in the
parts per million range. Since I usually have all my tanks planted, I try
to avoid adding too much salt and this dosage (well, actually closer to a
tablespoon in 40gal tank, since that was the one with the issue) helped
with my last case of nitrite poisoning. You can certainly add much more
safely if you're concerned and you have no plants. Just that you don't
always need quite so much salt as many webpages recommend to get a
beneficial effect for nitrite poisoning, heh. Many of those pages are
geared towards preventing paracites/disease like ich, so have a much
higher concentration of salt as a consequence.

While I'm thinking of my last case of nitrite poisoning, here's a
correlary piece of advice, consider it a cautionary tale. If you plan to
do any sort of vacation/travelling in the future, start to look for
someone now who is tank saavy, even if it means hiring a professional, to
keep an eye on your tank(s) while you are gone, particularly with a large
one like this tank. Don't rely on friends or family who don't know about
fish. I did and it was a complete disaster. I went to a conference (3 day
trip) and left my roommate to watch over the tanks (then just the 40g and
6g). Not only did she leave the AC off in 100+F weather (killing the whole
40g, 6g was just a betta so he survived the low water O2), she didn't
notice that the 40g filter intake was clogged up from the dead fish and
not flowing. So I lost the whole tank stock AND most of the bacteria
colony. I thought I had gotten it recycled fishlessly, but apparently only
got the ammonia colonies reseeded completely because I got a nitrite spike
(a bit over 1ppm) when I added 4 juvie calvus. Lost one in the process to
nitrite poisoning (they were in somewhat poor shape when I got them at
auction to begin with), but the rest recovered after a 50% water change
and some salt. But this was also a filter reseeding effort, so the nitrite
spike only lasted about a day since I already had some bacterial colonies,
just apparently not enough to handle the calvus. So moral of the story is:
roommates are evil, heh, and don't trust your tanks to novices. I've found
a professional pet sitter now who is a marine tank keeper. Worth the $20 a
day for her to visit to be sure I don't lose $200+ in stock.

Seperate question;
What do you think of water softening salt like;
Swifto Brand "Crystal Plus" water softener salt
20KG bag (44lbs) for $3.50
Improved Resin Clean Formula
Inhibits Rust buildup and stains
99.8% Pure Evaporated Salt
Compacted for Maximum hardness
High Purity Brine reduces maintenance

Even though it's 99.8% pure, i'm not sure I should use it,
what do you think? My LFS uses something like that
for years and he swears by it.

I'm not really familiar with the contents of water softening salt, so I
can't really say for sure if it would be safe or not. Probably wouldn't be
toxic or we'd be hearing a lot about deaths from people who fill the tank
from a tap that is on a water softener. I just don't have any use for that
much salt, so never looked into it. My 2lb box of rock salt from the
grocery store has lasted me over 2 years now, even using it for the brine
shrimp hatches, but I only have small tanks (40g, 29g, 10g, 6g) due to the
restrictions on tank sizes at my apartment complex.