counting rotifer density without a microscope

[mbbuna]

Hi - I need help with measuring the density of rotifers - without using a microscrope. I've read J. Wilkerson's book and tried her method but it's not working.
I think I might have too many right now but need something to measure it against. (I'm trying to raise saddlebacks).
Any advice would be greatly appreciated.
Thanks,
Barb

 

[phender]

If you have a syringe from a test kit or Joe's Juice, you can suck up some rotifer water, hold it up against a black background and use a magnifying glass to count them. 1ml syringes work great. That way you can just count the ones in a .1 ml section and multiply by 10.

 

[mbbuna]

thanks Phil

 

[Baalz]

I have never measured the density of my rotifers.. just to much work to worry about mundane things. Feed em well and harvest them regularly and they will be dense.

 

[mbbuna]

we probably will end up judging it by eye at some point but with out an kind of benchmark it would be a very wild guess

 

[Baalz]

Hit em with a flashlight.. If your saying to yourself "damn thats a lot of rotifers" then they are plenty dense.