Fish dying in SW tank

[AdamHorton]

I've had a few fish deaths recently and I'm worried about it. Here's all the details:

Tank: 150G SW tank, FOWLR for now. Cycled using pure ammonia in November 2009. There's a 20G sump and a 20G refugium for a total of about 180G in the system. There are about 250 pounds of LR in the system that I use for biological filtration. Also, a month or so ago I added a Tunze protein skimmer into the sump which seems to be working OK. If you need more details, there's a link in my signature to my fish blog, and the "tank specs" page contains a bunch of information.

Livestock:

Before - 5 damsels, 3 tangs, 4 Bangai Cardinals, 1 Cave Goby, 1 firefish goby, 1 bi-color blenny, 1 mandarin, 20 or so Nassarius snails, 1 Royal Gramma.

Over the past 6 months the cardinals have gone from 4 to 2. I can't be exactly sure when, since when they breed it's typical for them to hide on the rocks for a few weeks without me seeing them at all. Their behavior during this time can be pretty aggressive, so I chalked these up to aggression.

From March 9-15 I went on vacation. When I came back, I couldn't find the Bi-color Blenny. Since then, I've lost the Firefish Goby, the mandarin, the cave goby, and possibly the Royal Gramma. I haven't noticed any signs of sickness or anything from any of these fish, but I haven't been around my tank nearly as much as I should recently because of all the travel.

What's been going on:

I'll start with measurements that I took last night:
Ammonia: 0
Nitrite: 0
pH: 8.2
Specific Gravity: about 1.023 (refractometer)
Temperature: 80-90F (more explanation below)
Nitrate: about 200 ppm

So the red flags are temperature and nitrates, obviously. I should explain what's going on here. Over the past few weeks I had slacked on making my water changes. I eventually wanted to get my nitrates down to zero, so when I got back from vacation (last weekend) I put together about 60 gallons for a large water change -- this would be the first of many water changes.

Unfortunately, one of my trash cans failed and dumped 40 gallons of saltwater on my carpet/laminate floor. This sucks, but my homeowner's insurance covers it. So, no water change yet, but instead I've had fans and dehumidifiers running in my house for about a week (they are gone as of last night). The temperature in that room was about 95 degrees during that time. Between the unseasonably warm weather and one of my heaters which I suspect is going crazy (and is now unplugged), the temperature has been fluctuating between 80 and 90 degrees over the past couple of weeks. It's possible that this could be part of the problem.

Also, because of the increased temp. I've been topping off the tank a lot more than normal recently, which means possible fluctuations in Specific Gravity (though I can't see it being that significant). I try to keep it between 1.023 and 1.025 at all times, and that measurement (1.023) was made after a top-off of maybe 5 gallons (I had to travel for work this week. I got back last night and topped it off (and found some dead fish)).

So, nitrates, temperature/SG are the suspect things here.

There's one other issue that I don't think is related, but it might be. Two of the tangs have been sort of recently competing for dominance. It looks like they got in a bit of a fight while I was gone, and one of them (Buzz) looks like he got the worse end of things. He's acting like he just got put in his place, and it looks like he just got beat up a bit, but I didn't want to rule out that it's related to the rest of the problems. The best picture I could get is here:

http://www.adamhorton.com/files/buzz.jpg

It's not the best picture in the world, and he really doesn't want to show me his other side, which looks a bit worse. If this is aggression then I'll feel better, but if this is a disease, then he's the only one with symptoms.

Could all this be explained by temperature/nitrates/aggression? Or is there something else that could be wrong here? I really don't want the answer to be "start from scratch", but I'm afraid that it is. Any help or ideas would be appreciated. Thanks.

 

[crister13]

It's definitely the nitrates/temp. Just get the grates down from pwcs and keep the temp~80. Then get some fish!!!!!

 

[AquaRick]

Well looks like you hit the nail on the head. Temp and nitrates are ridiculously off the charts! =/

1) Temp: How is the water temperature now that you removed the suspect heater? What is the ambient temp in the room now?

2) Nitrates: 200ppm is just asking for fish death. What have your nitrates been historically? With a skimmer, the amount of rock you have, and what seems like a decent bioload your trates shouldn't be that high. What is your feeding schedule like? How much are you feeding each time?

 

[AdamHorton]

Thanks for your quick replies. I feel better knowing that nobody has told me to start from scratch yet

1. Temperature: I just got home last night from travel and turned on the A/C, so last night when I looked it was 88F, but the room temp was 90 or so and still going down. I expect the room temp to be down to 78 when I get home tonight, so I will continue to monitor the temp. Sorry I don't have anything more accurate, but things are just starting to settle down outside the fish tank...

As for what was going on with the heater, I noticed the temp was warm when I was feeding one night (my hand was above the water and I thought it seemed warm). I ended up taking a week or so to figure out which one it was (I have three small heaters) so between all of that business, the temp fluctuated between 80 and 90F.

2. Historically, with 20G water changes every other week, the nitrates never got higher than 40-80 ppm. I've only added the skimmer recently, and I'd say it's still sort of "warming up". It produces a decent amount of nasty skimmate, but not a whole bunch. I usually feed once a day, what they will eat in 2 minutes, but as much as I've been away recently (past two weeks) I'd say it's been about every other day, the same amount, on average.

There are a couple of theories I have as to why the nitrates are so high right now.

a) Obviously I've slacked recently on water changes. Between vacation, my most recent delay, and the slacking before that, I'd say it's been at least a month since the last water change. Even though they're usually small, I'm sure this is a contributing factor.

b) When one fish dies, the snails waste no time in taking care of the body before I can take the fish out (especially when I'm out of town). I imagine that with plenty of biological filtration available, this all gets converted to nitrates, which could lead to a spike.

c) I've heard that Chaeto algae can possibly leech nitrates back into a system, like when you trim it while it's still in the tank or something... well with all of this evaporation happening, the water level in the refugium has been getting lower than usual, which resulted in some of my chaeto getting stuck on top of the rock and kind of dried out. Maybe it leeched some nitrates back into the system?

Anyways, since I'm home this weekend I'll be purchasing some smaller trash cans to hold my water, storing them OUTSIDE until they're all ready, and making as large of a water change as I can. I'm wanting to get my nitrates down to zero anyways because I want to start getting corals for this tank.

Again, thanks for the help. If there are any more thoughts I'd certainly like to know. Do the marks in the picture look like anything more than aggression?

 

[tonedogz]

wow I've had some high nitrates but thats crazy. What test kit are use using, is it fairly new or old. How long has the tank been set up.

 

[Reeffanman]

When was your last water change and how much was it?

 

[Andy Sager]

I'd check your PH again as well. Normally, a rise in nitrate causes a drop in PH. What was the PH reading before this incident?
It sounds like the life in your refugium isn't doing it's job at the moment. You may want to check into that as well. You may need some more macro algaes to keep up with the volume of nitrates being produced.
The lose of any or even all of these smaller fish (sans the tangs if they are large fish) in such a large volume of water should not have spoiled the system. Not to the degree the readings are. You reallly need to address the system then the fish. IMO

 

[AdamHorton]

I'm using an API test kit, which I trust. I had to dilute the sample before I could get any real reading at all. The tank was cycled in November 2009 and has been running smoothly ever since. I did move in December 2010, but I didn't have any problems related to that.

The last water change was roughly a month ago, and at that point it was 20 gallons every other week.

pH is relatively stable at 8.2 and has been throughout as far as I can tell. The chaeto ball in my refugium has basically died, so yes, I need to get new macro algae. I'm thinking of getting something else, my LFS sells caulerpa, but I need to look into that.

I'm doing at least one large (60 gallon) water change this weekend, and I'll be doing them as often as I can until the nitrate readings get to 40-60 (and hopefully down to zero).

 

[mr_X]

I would invest in a chiller or at least leave the A/C on in that room. I would also be doing large water changes to bring down the nitrates. If your algae died, I doubt the addition of more algae would do anything positive. Not until you get the parameters closer to "reasonably safe". Otherwise the new algae will just die and add to the problem.

 

[Andy Sager]

I would invest in a chiller or at least leave the A/C on in that room. I would also be doing large water changes to bring down the nitrates. If your algae died, I doubt the addition of more algae would do anything positive. Not until you get the parameters closer to "reasonably safe". Otherwise the new algae will just die and add to the problem.

Ditto!!
Good point Doug. I failed to mention the order to address things

 

[AdamHorton]

Now that all of the equipment is gone, the temperature has been stable at 76-78 degrees all this weekend. I just completed the first large water change and took a nitrate reading: it looks like it's at roughly 100 ppm. I'll continue to do these large water changes until the reading gets below 40 ppm (and I'll probably update every time I do).

What would you say is the minimum time I can mix saltwater before I can use it for a PWC? I usually start mixing right after a PWC and there's at least a week before I change again, so it's never been an issue, but I'd like to do large PWCs daily if I can, and I only have 20-gallon containers to use...

I don't plan to stop until I get the nitrates down to zero stably. I know I'm going to need something in my refugium to help out with this, and I'm wanting to go with something other than chaeto. I'll probably need a better light as well. I understand that I won't be actually implementing this until the nitrates get below 40 ppm, but if I need to order equipment, I'd like to know what people recommend, especially if they have their nitrates at zero without a ton of maintenance. Does anyone out there have any suggestions?

Once the nitrates are at zero, I'll probably add some fish back in as well.

 

[melosu58]

If you are going to be doing large PWC`s I would at least let it set 24 hours. That way you know the new water is stable and thourgly mixed.

 

[AdamHorton]

I finished my second large water change last night, I've been doing 60 gallons every other day. I took a nitrate reading and it's between 40-80 ppm. I'm going to keep this pace up until the nitrates are below 40 ppm.

Also, Buzz (the fish from the picture) is finally looking better than he did previously. Now he's not doing his hide-in-a-cave-all-day-and-only-come-out-to-eat-a-little-bit-then-go-back-and-hide thing anymore, he's actually out swimming with the rest of the fish. The more I watch him, the more he's behaving like he just got put in his place (really badly) by another fish.

At the moment, none of the remaining fish are showing any other signs of stress or disease, and the tank parameters in question (temperature, nitrates) appear to be at stable levels that are somewhat acceptable, though the nitrates are still a work in progress. Temperature has been between 76-80F.

Once I get down to 40 ppm nitrates, I may have some questions about how to get that number down to zero, but I think that's a topic for a different thread. Thanks for all of the help.

 

[uh.oh...]

0 nitrates can cause a coral bleach/brown out. How long have you been without a skimmer? I think its something like at 11 months for a tank without a skimmer you start to run into issues, and at 13 you're just asking for trouble. But if you were doing regular water changes of 60g plus I wouldn't imagine that to be an issue. I wouldn't rule it out though. Glad you have one now

 

[AdamHorton]

The tank was cycled in November 2009 using pure ammonia. I moved in December 2010, which involved a nearly 100% water change. I got my skimmer in late January 2012 and it has been running ever since.

Regular maintenance throughout this entire time was a 20-gallon PWC every week, sometimes every other week. As I said above, over the past month, that has slacked off, and it's been just this past week I've been doing 60-gallon PWCs every other day to bring the levels down.

There are no corals right now, but as soon as things settle down and I have everything at acceptable levels, I want to get some. My knowledge of what it takes to care for corals (beyond what is required for fish) is the following:

"nitrates = bad"

Judging by your post, even that may be a generalization. I certainly have a lot to learn about reef keeping, that's for sure.

 

[scottkraft]

now that you are getting the trates down might want to go to smaller pwc to see if nitrates go up and you have another issue you have to ID.
Definately get some Macro algea into the fuge as well any is better than none. Some are better but... I use a reptile lite with a CFL grow lite for my 30 gal fuge and it does a great job , low heat and lots of lite. Got mine at Petsmart for $30something.
Melosu58 is right at least 24hr after adding salt (as if i have anything near his knowledge)
Scott
90gal reef
40gal reef
still to come 270 reef

 

[Andy Sager]

Minor correction....

There are no corals right now, but as soon as things settle down and I have everything at acceptable levels, I want to get some. My knowledge of what it takes to care for corals (beyond what is required for fish) is the following:

"nitrates = bad"

When or if you do decide to put corals into this system, you do need to understand their requirements a bit more as you suggested. The correct phrase is not " Nitrates= bad" it's "Too many Nitrates =bad". The algaes inside the corals (that give them those beautiful colors btw ) need some nitrogen in the water to feed off of. They don't just feed off of the light. They use the light to photosynthesize the nitrogen in the water so if there's no nitrogen (in the form of nitrates) there's no food. That's bad!!!

But you sound like you are on the right track. Keep us posted

 

[AdamHorton]

I did another large PWC on Monday night and took a nitrate reading immediately after. The nitrates are now between 20-40 ppm!

At this point I plan to go back to regular tank maintenance and keep an eye on the nitrates. Also, I'm hoping to get some macro algae back into my refugium to help with keeping the nitrates down.

I got a new refugium light: JBJ Macro-Glo Adjustable Refugium Light

I guess it's a strange thing about my refugium, but the water level can get down to about 6 inches deep, but if I turn off the pump, the water level can get up to 12 inches. This means that the light has to be 8 or so inches above where the water is most of the time, just in case the return pump fails. I don't know if this matters or not, though.

Is there some type of macro algae that would be best for my fuge? I can get chaeto at my LFS, or I could order something else if that would be better.

...I may start a new thread about this, though, since it looks like I'm not losing any more fish and I've taken care of the problems here.

 

[OniTweak]

Here is some decent info on Macroalgaes for your fuge.

Best Plants and Algae for Refugia - Part II "Vegetable Filters" | Reefland

I personally have always been a fan of Chaeto.

 

[uh.oh...]

chaeto is fine. Caulerpa just requires more work, but also is a good choice. I think of chaeto as "set it and forget it" Mangrove tress are my favorite, and I'm trying to nurse one back to health right now...but its a struggle. They aren't really that efficient at removing nutrients with just one, i think you need 1/4g to make any real difference. My eventual goal is to have a little 2 foot mangrove tree living next to my fish tank, kind of like that Spanish guy with the awesome coral operation... or maybe he was from Portugal.