2 fish deaths in 3 weeks

[David S]

Hi Mark

Are you using the same salt since the move,could it have been contaminated with anything?also how old is the new place as some older places still use lead piping for mains water which can't help,just guessing now though.

[pat8you]

I have only read through the last couple of posts so just ignore this if it has already been tried. If there is something in your salt mix and it somehow got contaminated i would try running some activated carbon for a couple days to try and pull what ever it is out of your water. Might help the fish that are in the tank. Sorry for all your troubles. Hope you figure it out.

[MarkW19]

Thanks for the replies guys. My Royal Gramma gave up after approx 3 hours of deep breathing on the bottom; my green goby was actually okay and not affected (thought it was), and my yellow clown goby was breathing extremely fast, in the same spot, for almost 5 hours. This morning, I'm pleased to report that he now seems absolutely fine. I'm really pleased about this, as he's now the only surviving fish from my original tank. I just need to get to the bottom of this now before the next waterchange!

Yes, I use the same salt I always have. I guess it could have been contaminated somehow (perhaps a bad batch?); it's stored in an air-tight container under the sink, no damp or anything, dry, room temperature. Is there any way I can test if there's a problem with the salt?

The house is approx 20 years old; not sure about the piping. Wouldn't anything like that (e.g. metals) show up in the TDS test thought? If not, again how can I test?

Pat: I'll run carbon now, thanks.

[thincat]

Hi Mark, I really have trouble reading long post so I only scanned over the details.When you moved to the new tank did you reuse the sand? That's the only thing I can think of is when you do a PWC you might be stirring up the sand and releasing toxins that in time is taken out by your filter. Pats Idea of running carbon is spot on so give that a try.

[MarkW19]

Originally Posted by thincat

Hi Mark, I really have trouble reading long post so I only scanned over the details.When you moved to the new tank did you reuse the sand? That's the only thing I can think of is when you do a PWC you might be stirring up the sand and releasing toxins that in time is taken out by your filter. Pats Idea of running carbon is spot on so give that a try.

Hi, no I didn't reuse the sand, I used brand new ceramic media (due to the filter, I would have preferred live sand), which seems to be doing its job as there's no ammonia/nitrites, although nitrates are high at 40ppm, but consistently so.

I siphon out the tank water when I waterchange, and barely agitate anything (e.g. the substrate), but I guess if there's any food/detritus contained in the substrate/in the rocks etc., that this could be slightly agitated during a waterchange. BUT, would this not show up as ammonia, either immediately or over a couple of days?

[thincat]

Yes, but it could also be a metal that your test is not made to detect. Where did you get the sand from? So many questions, but that's the only way to weed out any one thing.

[mrg02d]

I find it strange that this happens when you do a PWC. Id suspect either the salt or the water. Maybe get some new salt and see if it happens again? Maybe your RO/DI filters need changing? Maybe the TDS meter isnt reporting whats really there?

Id try new salt and some bottled water (DI) and see if things improve. That way you know its not the salt or the water.
Matt

[MarkW19]

I guess it is either a problem with the salt, my RO water, or something that gets stirred up in the tank (in the media/rocks) when I'm doing a bit of cleaning. Although I would expect this to show up as ammonia?

The RO filters should be fine (only a few months old), but yes you could be right about my TDS meter. I'll recalibrate it.

Are there any other tests I should be doing to look for any other contaminants in either the new salt or the tank water?

[thincat]

What temp. is your tank at?

[MarkW19]

Originally Posted by thincat

what temp. Is your tank at?

27-29°c

[thincat]

Well, mark this is the USA and we deal in degrees and I can't seem to find my conversion data.

[mrg02d]

Hahaha....25C is room temperature. 27C is 80F, 29C is 84F

Temperature is fine, but id not let it go over 82F.

Matt

[David S]

Originally Posted by thincat

Well, mark this is the USA and we deal in degrees and I can't seem to find my conversion data.

thincat we use degrees as well degree centegrade Ha Ha :p

[MarkW19]

Well, I've ordered a fresh batch of salt; and I'll make up some fresh RO for my next PWC. I'll also recalibrate my TDS meter to make sure it's showing accurate readings.

Apart from this, are then any other tests I can do either in the new SW before I put it in the tank, or in the tank after a waterchange to try and find out what's happening?

[MarkW19]

Guys, on another note, yesterday I noticed a lot of worms at the bottom of my tank (look like bristleworms, approx 15 of them of different sizes); never noticed these before in this tank or any before.

I guess they're not the reason for the waterchange issues, but should I be getting rid of them? If so, how?

[thincat]

Bristleworms are not normally a problem. I noticed that after I added a bi-color pseudochromis all my bristleworms disappeared.

[MarkW19]

Thanks, I'll keep an eye on the bristleworms.

I've just got some new salt to see if it was that, and I've got some TDS calibration solution on the way to test/recalibrate my TDS meter, so I'll try a water change when this arrives and will see what happens to see if I can rule these two things out.

Are there any other tests I should be doing on the new water, or after the waterchange if problems develop again, e.g. oxygen etc.?

[thincat]

The main thing is to be consistant about what you do. Keeping your parameters stable will go a long way in keeping a reef tank.
RO/DI water, 1.025 SG, 0 ammonia,0 nitrite, keep nitrate as low as you can 20ppm's or lower, if you are keeping corals the closer to 0 the better, temp. 79 degrees to 82 degrees, again the more constant the better. If you have an algae bloom, check to see if it's the food,(frozen can be a problem) and you could check for PO3.

[MarkW19]

Hi Thincat,

Thanks for the reply. My water parameters are stable and always have been (I use RO water @ <002ppm TDS), 1.025 SG, 0 ammonia/nitrate, and nitrates are approx 30ppm (no corals), pH 8.2. Temp is consistent. I feed high quality pellet/flake food usually, with the odd frozen as a treat. I will check for PO3 as well, as I have a bit of algae (not a huge amount).

Regarding the problems I've had with fish dying at each of my last 3 waterchanges, I'm going to recalibrate my TDS meter, make up some new RO, and I also have a fresh batch of salt to try, so I can at least rule out the new water. Is there anything else I should be testing for in the new water other than pH/temp/SG/TDS (before salt), to see if anything else has leeched into the water/bucket etc.?

If the new sw is okay, another issue may then be that I'm stirring up/upsetting something in my tank when I do a waterchange, although as discussed this isn't showing up as ammonia or anything that I've currently tested for, and things settle down within an hour or two. Again, is there anything I should be testing for here to see what's happening, that I'm not already?

[thincat]

You could check for copper. Another thing If you don't have a sump, try adding your new water slower so as not to stirup the sand. Stirring up the sand may be causing hydrogen sulfide (H2S) gas to be released into your tank. This is caused by dead spots in your tank. you could try to run another ph to move water around to keep this from happening. How deep is your sand? Have you added anthing new to your tank.