Water chemistry worries Sadly, some of our TIC teachers (and I) are losing sleep over water chemistry challenges. A good example is what's going on at Mt. Anthony Union Middle School, where Emily Hunter has struggled for many days to bring down high nitrite and nitrate levels. Starting about five days ago, Emily's nitrite hit 3 ppm and her nitrate reached 80 ppm. Over the next few days, Emily did several water changes, and her nitrate dropped some, reaching 20 ppm today, but nitrite remained high, even registering 5 ppm a couple of days ago. So what can we advise Emily?
Dropping the basket at SLC Here's a video that Danielle Levine, of Schoolhouse Learning Center, sent me of the day she and her students lowered the breeder basket and released their fry into the wide world of their 55-gallon tank. Danielle also provided these photos of her liberated fish. Thanks for those submissions, Danielle! Fishy infections and other problems Along with water chemistry challenges, some of our schools have been trying to deal with tank fungus and fish infections. This message from Audrey Halpert, at Albert Bridge School, provides an example of one such problem. I am having a massive die-off. Most seemed to be up and feeding well for two or three weeks then they started to get skinny and lie on the bottom of the basket. The dead and dying each have white patches that look like fungus on their operculum. We have lost 20 of our 70 and there are 10-15 more sick. I have tried to separate sick from healthy in separate baskets. Our water parameters are fine except the high Gh. What can I do? I don’t want to lose them all. Is this ick? By the way, Audrey's water chemistry numbers were all perfect. Here are a couple of pictures of Audrey's fish with their "white patches." I asked Audrey if the white stuff looked like Saprolegnia. She responded with: Joe, I wouldn’t say it's that cottony or fluffy, but maybe I should scrape some and look at it under a microscope. It definitely shows up on the operculum, not on other parts of the body yet. It seems to affect their breathing. I'm afraid I may lose them all. After she looked at it under a microscope, she also though it didn't look like ich, which two different experts on the TIC/SIC network suggested it might be. Stumped, I sent Audrey's photos to Dartmouth Professor Robb Cramer. He sent me this reply: Based on those 2 photos, it does not look like a fungus to me. It is hard to say what it is based on those 2 photos. The lack of feeding indicates something is wrong, but super hard to figure out the cause with limited information. There is some chance it is a disease called Columanaris, but just speculating. My global advice in these situations is to do a 50% water change ASAP. Clean the gravel with the siphon. Separate any sick fish and put them in another small tank if you can. Audrey came back with the photo below and this: It’s odd that the patches are always on the gills. I may remove the dying to a home tank in a cool workroom I think they are goners any way. Even though things weren't going well, and I hadn't been able to be helpful at all, I complimented Audrey on her photography skills. See these closeups (the second is taken at a later date). Robb recommended two treatments, first an API fish antibiotic and, if that didn't solve the problem, an API anti-fungal treatment. They look like this. After all Audrey's worrying and Robb and Audrey's efforts, it's not clear that her fish are going to make it. Most of these long-distance consultations aren't this challenging and work out better. By the way, when I complimented Audrey for the great closeup photos she was sending, she said that she took them using a ProScope attachment for her iPad. Here's what that $149 device looks like. Two-headed trout still with us! Mary Fiedler, of Cambridge Elementary School, sent this picture on 3/15/18 of her school's two-headed alevin. Still hanging in there! Too much suction! Jaclyn Bristol, of Guilford Central School, sent me this e-mail. We have a high number of fish dying this week. It looks like even with our filter end covered, they get sucked onto it and cannot get off, resulting in them dying. We have moved them back into the cribs for now. We are down to 77 fish. What are the rough die rates? I told Jaclyn that the problem was that her fish weren't yet strong enough to swim off the filter-end netting. Her decision to put the trout back into the breeder basket was a good one. That way they can get stronger and should be able to resist the suck of the filter in a week or two. Another option is to reduce the rate of flow of the filter. (We normally urge teachers to keep their filters at maximum flow, but this situation is an exception to that rule.) For those who have the AquaClear 110 filter, page 12 of your Instruction Manual contains this image, showing where the nob is to adjust flow rate. (It's that red thing poking up!) Most other filters will have similar ways to adjust flow rate.
Regarding Jaclyn's question about mortality rates, I answered that the 2016-2017 survival rate was 59% and that the rate last year (2017-2018) was 47%. Here is a ranked list of the principal causes of mortality during 2017-2018. The number at the end of each line is the number of schools (of the 21 completing a Survey Monkey questionnaire I sent them) indicating that that particular item was a principal cause of their fish losses.
This is why we worry so much about catching the swim-up stage. Send your swim-up data! We still need to hear from more schools.
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Joe Mark is Lead Facilitator of Vermont's Trout in the Classroom program.In June 2012, I retired after 40 years in higher education, having spent the last 32 years of my career as dean at Castleton. One of the first things I volunteered to do in retirement was to work with a parent-friend to help the Dorset School, where his kids and my Vermont grandkids attend, start a TIC program. Gradually that commitment grew into my current role, which is both demanding and highly rewarding. Archives
December 2019
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