How long can you keep a starter culture in the fridge?And this is why you always split your starter culture into multiple batches. As you can see one of the three is quite contaminated and didn't grew as dense as the other two.
I will start the next batch with No. 1 or 3 depending on which looks better up close.
This will probably depend on the plankton species and overall purity. I would say a week or two if you shake it every day at least once. You will lose cells in the process so growing a new culture may take a bit longer than a fresh starter, but it should work.How long can you keep a starter culture in the fridge?And this is why you always split your starter culture into multiple batches. As you can see one of the three is quite contaminated and didn't grew as dense as the other two.
I will start the next batch with No. 1 or 3 depending on which looks better up close.
Using an excess of thiosulfate is important to ensure there is no chlorine left. It usually doesn't affect the cultures much.Did I kill them all?
So, I started my first ever culture yesterday, about 24h ago: https://www.reef2reef.com/threads/growing-copepods.1163548/post-14465201. I am moving the discussion here not to messup with the original thread about pods. On the photo in that post, from the left:
All looked nice and fluffy when I went to bed. 8 hours later, today morning (I am in AU) all 3 cultures were crashed. Tetra and Phaeo were all on the bottom, Nanno was holding a tiny bit better, but still almost all cells on the bottom. Air was pumping, light was on (continuous light). I hopelessly swirled the bottles and managed to resuspend all 3 cultures. All were showing clumps. Two hours later I repeated the swirling, clumps disappeared, looking better. I repeated swirling once or twice more through the day.
- Tetraselmis
- Phaeodactylum (a diatom)
- Nannochloropsis
Now, after approx 4h since last stirring Nano actually looks almost fine. I would be proud, if I did not see it on the bottom in the morning. Tetra show gradient - more cells close to the bottom, some on the bottom. Phaeo looks the worst - clear colour gradient, lots of cells on the bottom, clumps visible during swirling. Clumps dropped back to the bottom after swirling stopped. This is how the cultures look 20 mins after last stirring:
All show some clumps, Tetra more than Nano (Nano on the right), Phaeo (in the middle) show most clumps. But still... some cells seem to be suspended. Maybe they make it? Anything I can do to help them? Or, it's over and I am abusing the corpse?
In the morning, I swallowed my pride and consulted The Wife. She is a real-deal wet-lab rat, not a dry-lab nerd like me. Plus converting honey into mead is her hobby. She scorched me for not following @EnterName autoclave advise, but using some chlorine crap from supermarket, and she questioned my integrity when I admitted to not temperature acclimating the fridge-stored cultures first. Yeah. All deserved. (I neutralized the chlorine with sodium thiosulfate, confirmed 0 with a chlorine water test strip. I have likely added more thiosulfate than it was needed.)
I wonder if I should give them dark time tonight, or not? Should I move them away from the light to lower the exposure and the temperature?
In theory you can just add more sterilized water with fertilizer, but I prefer to start with clean and sterile bottles. As most people don't work perfectly sterile and don't buy expensive sterile cultures, there will always be some growth on the glass over time. Using clean bottles instead of letting this stuff grow helps to keep the culture stable and reduces the amount of contaminants.Great writeup and a thank you for helping me get me started with Nannochlorpsis.
Now I have a question that I can't seem to find an answer to. If you start with larger container(s) and when the batch has matured can you simply add more salt water and another dose of F2 then continue on?
I was thinking of getting the salt water ready and letting sit in the same room until the temperature matches then doing this until the quantity is large enough to start feeding my copepods without worrying about running out and having to reorder another starter.
For info I started 2 days ago and the 50ML starter I bought was very light green. After starting with 500ML of salt water @1.023 and dividing the starter in half it was almost clear and I was a little worried but both 1 gallon tanks are now darker than what I started with so I am hopeful I can continue this by adding another 500ML and F2 each week until they are almost full.
