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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, March 11, 2014 1:17 AM
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Since you asked...... Zach, your math is overall good, except that you are using too many significant figures in your calculations that you almost certainly cannot support with facts. For example: Your "about 12 cups", when converted to mL, well, yeah, sure, if I Google "convert 12 cups to ml", then I, too, get an answer of 2839.06. However, in order to use such a precise number, then you would HAVE to be able to measure your cups to within 0.01 ml = 0.0000423 cups accuracy. Are you really asserting that (A) the measurement markings on the side of the jar are that accurate, and (B) that you can visually discern the meniscus with that accuracy, and (C) that the meniscus was exactly on the mark on the side of the jar to that degree of accuracy (never mind the effects of temperature and barometric pressure on the volume of the liquid)? I very seriously doubt all three, and you would need all three to support using a number like 2839.06 in your calculations. Since you used "about 12 cups" in reference to a VERY coarse measurement marking, then you can probably honestly claim just 2 significant figures, *maybe* 3, in the volume measurement, regardless which units you are using. So, re-doing the math, I get: 2840 * 2,910,000 = 8,260,000,000 or even 8,300,000,000 (notice that even though the answer on the calculator when you multiply 2840 * 2,910,000 is 8,264,400,000, you still don't get any "free" significant figures out of the deal. Your numbers are only as accurate as the accuracy of the least accurate number(s) you are starting with). Let me give you another example. As I write this, I am sipping a glass of wine. That glass has a diameter at the mouth of 6.3 cm, which is the most accurate measurement I can make with the tool available to me (a metric ruler with mm divisions). If I wish to calculate the circumference of said glass, would you agree that I can say with any real integrity that the circumference is 19.7920337176 cm (the answer I get when I Google "what is 6.3 times pi")? I hope that you would agree that, considering the relatively coarse units of my original diameter measurement (6.3 cm), at best, I can only claim to know the circumference to within two significant figures as well. Accordingly, I can only honestly estimate the circumference to be 20 cm, even though I might be able to estimate pi to many, many decimal places. The extra significant figures in the value of pi I use do not make up for the relatively inaccurate measurement of the diameter my calculation is based upon. Other than that, your math looks great!
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, March 11, 2014 7:48 AM
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Thanks for the refresher on sigfigs Jim! Never really understood them in chemistry since my teacher flew through them in a day. I'll be sure that any more cell counts I do, I'll use the right significant figures! Also, as I mentioned before, I'll be splitting this afternoon, once I get back from school. I think I will still keep the 3 cultures, since I don't wanna make too much algae with nothing to do with it.
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, March 11, 2014 9:52 PM
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Also, on another note, EXPLOSION last night. The lights do not come back on until after I leave for school, thank you daylight savings... ANYWAYS, did another cell count. Let's see if I do my math correctly this time: Section 1: 1,088 cells Section 2: 1,007 cells Section 3: 984 cells Section 4: 1,046 cells Avg cell count: 1,031.25 cells 1,031.25x10^4 = 1.03125x10^7 cells/ml, or 10,312,500 cells/ml Sig Figs Allowed: 2 New Cell Density: 10,300,000 cells/ml or 1.03x10^7 Total Cells: 2840 x 10,300,000 = 29,000,000,000 cells, or 2.9x10^10 As you can see from the data above, this morning (the two hour dark period,) had a TREMENDOUS amount of growth, in a short little two-hour light/dark period. I don't think I actually need to do the lighting test, seeing as how these guys are doing great on 22 hours. I also believe I have a standard culturing guide for these guys, and they are fairly easy and very fast growing. I'll do some nutritional tests in a few weeks when I grow enough. Also, would it make sense if I'm using them to culture them in a larger container and just top-off the water with freshly-microwaved water instead of generating a new culture? (*next experiment that I will be doing once I find a good container*) Culture Guide: 1. Add 2x Guillards F/2 formula per 100ml of culture water 2. Heat in microwave until 212F has been achieved 3. Allow cooling until room temperature 4. Split algae into containers 5. Run airline into culture with a mild-turbulent flow 6. Have warm lights on the culture running at 22 hours on, 2 hours off 7. Split every day or two, or until the jar has a light green tint to it 8. Repeat 2-6 for every split
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Saturday, April 12, 2014 8:46 AM
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Well, might as well update this again. I didn't split a culture for two weeks to see what happened. It got VERY green, almost to the point of where it looked black. Tried splitting it yesterday morning, and this morning it looked like a healthy green culture. These guys can clearly take some laziness by their masters!
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, June 17, 2014 7:50 AM
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Culture is still doing good, and now that the species data was approved, time for some reports (thanks Matt!) I'll get some photos today for the continuation report.
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Sunday, July 27, 2014 3:36 PM
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So, I still need to get those continuation photos for the report. Would just a picture of the jar with the algae in it do the job? My Celestron 44340 broke, and the replacement will be here sometime, I have no idea when since it is on back order apparently!
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Sunday, July 27, 2014 11:46 PM
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Micro pics are best but get what you can.
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Saturday, August 16, 2014 12:38 PM
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Ok just got the microscope in yesterday, I'll have the photos up by the end of the weekend
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, August 19, 2014 6:01 PM
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Does this Dun. turn red at any point, like heam. does when stressed? I know Dun. salina makes a red pond... SF Bay... ponds where SF Bay Brands used to harvest artemia before the landswap between the state and Cargil.
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Tuesday, August 19, 2014 8:16 PM
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No, I have not experienced any red Dunalia at all. When it crashes and stressed, the algae just sticks to the walls and the rest of the culture is either clear or yellowish (Iso is on a floor above it, but haven't noticed any contamination when the culture is doing well.)
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Re:Culture Journal, Species: [Dunaliella tertiolecta]
Friday, October 3, 2014 11:56 AM
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Well, we're not sure if we have Tetraselmis or Dunaliella, so unless I can borrow a microscope from my school to actually figure it out, I'm going to order a new culture.
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