Last week Bob Wible reported that the Lincoln Community School discovered their KH (carbonate hardness) had plummeted to 35 and that their ammonia was 4 ppm. PH was 7.6, and nitrite and nitrate were 0. When Bob retested KH after adding baking soda, he found it was 214 so assumed that the earlier test might have been an error. But this is a good reminder that teachers (not young students) should be checking KH at least once a week. KH can decline over the course of the TIC project; when it does, pH can become unstable, which stresses the trout. For more information, read the article titled "Baking soda, alkalinity, and carbonate hardness KH," which can be found in the Water chemistry and trout health folder (link below).
Lincoln's ammonia reading of 4 ppm could be dangerous, but they're not the only school to report elevated ammonia levels. The ammonia in Lisa Marks's Ludlow Elementary School tank has been reading 3 ppm for a while.
Two types of ammonia
The API freshwater test kit that we use measures two types of ammonia (in the same test), ammonia and ammonium. The former is very bad for trout, but the latter isn't harmful at all. There's almost no way to tell which type is elevated. (To learn more, read the "Article about relationship among ammonia, pH, and temperature," in the Water chemistry and trout health folder [link above].) I said there's almost no way to tell which ammonia you have. While this is not foolproof, the appearance of the fish themselves may help you decide. If the fish are active and if you think they look "happy," you're probably registering ammonium, not ammonia. If they seem lethargic, sick, appear to have taken on a dark coloration, or especially if there gills are redder than they have been, any of these might be signs of high ammonia levels.
Trout in the night
Do any of you dream about your fish or, even, have nightmares? I hate to admit it, but I occasionally do. This past Wednesday night, for example, I dreamt about the fish in Ed Robbins's tank at MRUHS. In my dream, he had many hundreds of big, beautiful fish. They were traveling tightly packed together in massive schools that swarmed at high speed around the tank. What surprised me, though, was that they were in their spawning colors, the way mature brook trout look in October. Even in my dream I knew that it was early spring, not fall. Hmmm?
And then Thursday night, I had a less pleasant dream about Lisa Marks's fish at Ludlow Elementary. Her fish didn't look well. In fact, one enormous brookie--it had to be at least three pounds!--was prostrate on the gravel, close to death. I could see, however, that its left eye was still bright. Later I was thrilled to realize that I was only dreaming and that, as far as I know, Lisa's fish are doing well. Whew!
What do we hear from our schools?
From Castleton Village School's Guy Merolle, I got this:
All is well here. We have lots of healthy looking trout. We have also reached "the cliff," and weaker trout are dying off at a high rate (see population curve: https://sites.google.com/a/arsu.org/mr-merolle-s-website/our-brook-trout-1). I have started putting sickly looking trout into "sick bay," where they may have a better chance of getting food, and where they will be easier to find and remove if they perish. We still have not detected any ammonia or nitrite, but the nitrate is soaring. Our hypothesis is that our aquarium started with a high level of healthy bacteria, perhaps they were dormant over the summer. Ammonia and nitrites get consumed as quickly as they are produced.
Karli Love at Dorset School gave this update.
Dorset School is holding strong with about 40 fish. LARGE and HUNGRY. Frequent water changes, adding nitrifying bacteria and lots of siphoning seem to be keeping our trout happy!
Kaitlin Cioffi-Grote at Poultney HS said this:
PHS fish are doing well. We have been doing our water changes and feeding our free-swimming trout. They seem to get bigger every day!
Keith Harrington, Poultney Elementary, contributed this report.
Our trout at Poultney Elementary School are doing very well. Since we let them out of the breeder basket we have found just a few fish that did not survive. All of them were significantly less developed then the others, which tells me they either were not ready to be out of the breeder basket, or just never learned to eat. Those cases have been few and far between though. We have well over 100 happy healthy trout that are growing and developing like crazy. We did have ammonia spike to quite a high level at one point, but after some serious vacuuming and water changes it stabilized. Our pH regularly runs about 7.6, and all other levels stay pretty steady. The mesh over the entrance to the filter works well, but we have noticed that uneaten food tends to gather on it and we need to change it or take it off and clean it every week or so. It could be that I am just feeding them more than I need to. Overall we are very pleased with how it is going. We hope everyone else is having great success.
Finally, also from Bob Wible, I got this:
I have one tank that is dealing with cloudy water. I'm thinking over feeding!! Am trying to get water test numbers.
My response follows.
Check out the "Water chemistry and trout health" collection on the Web site (link above) and read the article titled "Cloudy water, high ammonia levels, and the nitrogen cycle"; also see this:
Troubleshooting | www.troutintheclassroom.org and search for "cloudy."
Be well! And let's hear from you.
Joe Mark, Lead Facilitator, Vermont Trout in the Classroom
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 Jim Mirenda 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.