joneill809 Wrote:As a newbie I got burned by bringing in hydei cultures with grain mites from a commercial vendor. Now I'm working on clearing them out. I've implemented a few practices that I picked up from a variety of sources (these are not my ideas, just what I am doing):
- Keep only 4 of each culture, max of 5 weeks (typically toss at 4 weeks)
- Was using mite spray on paper towels, switched to diatomaceous earth on tin foil in one set, trying mite powder in second. I have not seen cross contamination of the grain mites from the hydei to the melanogaster yet...
- Set flies in 32 oz cup with powder (either expired supplements or cheaper bone meal powder) for 5 minutes prior to placing in culture. Sift through coarse strainer for hydei, flour strainer for melanogaster. This has visually helped with grain mite reduction in hydei - doubt it would be effective for melanogaster as the flour strainer is not coarse enough to let these giant mites through. Expect fly losses during sifting.
- switched to coffee filters from excelsior. I've seen different threads commenting on a higher rate of grain mites within excelsior based cultures.
- Just implemented - trying alternate media from a different source - claims to be grain mite free.
- Just implemented - trying in-media MiteBeGone1 and 2 in a subset of cultures to explore impact.
I have not seen another mite "boom" (I literally had an inch of mites in a 32 oz culture cup) since I started tossing cultures more aggressively AND powdering / sifting. Now I'm working on elimination. I should note that I have seen regular mites consistently in all my cultures. I took on all this activity due to booms in these giant grain mites and a fear of them spreading. I can't seem to attach pictures to the post - I'll upload them to the gallery and link from there so you can see the difference.
I'll post again once the in-media treatments are underway. Tell me if I'm nuts with any of these courses of action - I'm kind of viewing this as a challenge to see if I can aggressively control / eliminate a grain mite problem for the good of the hobby, so I'm hesitant to just pitch everything right now. I am starting a separate set of "clean" cultures in a different room from a different source just in case.
So it's been a while and I've had quite a few "do overs" on my culturing strategy. Overall, I'm not sure the in-culture chemicals are making all that much of a difference. I was able to reduce my mites problem (sorry, qualitative anecdotal evidence only) primarily through two mechanical processes.
Dust, sift, crawl
First, dusting all flies prior to introduction into the culture to dislodge mites from the flies. After dusting, I sift using two different strainers. This method has as far as I can tell nearly eliminated all mites from my hydei cultures (regular and golden) but I still get them in my melano cultures due to the challenges of finding a strainer / sifter that catches the melanos but lets the mites fall through. Over the path month I refined the method for mite removal from the melanos by dusting, sifting, then allowing the melanos to crawl over the edge of the sifter before dumping into the culture.
Wipe downs
The next change in culture management has been a daily wipe down of the outside of the cultures. Sounds silly, but I noticed when I picked up a culture I could feel bumps on the outside that were mites scaling the culture walls. They seemed to be making it across my mite paper (perhaps crawling over dead mite carcasses?
). I discarded the heavily contaminated cultures, then diligently wiped down each culture every morning with a Clorox wipe. I'm at the point now where I can rarely detect a bump on the outside of the culture, and my yields have stabilized.
Next up, ditching chemicals
Once I reach a steady production regiment that is nearly mite free I'll back off the in media mite control chemicals but keep the mechanical controls in place.
Anyone else using mechanical separation strategies?
