kazaa81 - 9-6-2006 at 06:40
Hi,
I was wondering if it's possible to buy diatoms and/or radiolarian cultures. I think it's quite difficult to maintain these microorganisms alive, but
it might be worth a try.
The solutions I came closer was buying diatomaceous earth, but these diatoms are dead since some time!
Here http://www.sciencestuff.com/prod/PreparedSIndpro/Bio1005
says about an undefined quantity of mixed diatoms for $2.45....
About radiolarian, instead, not even a thing...just a site quite good for exchangin opinions with other interested
http://www.radiolaria.org
kazaa81 - 10-6-2006 at 04:31
Maybe I can plan to grow diatoms from fresh water, not or slightly treated (by water sterilization)?
Interesting things about what diatoms can need to grow is found into a commercial aquarium cleaning product, to eliminate diatoms 
quite strange...
from http://www.algone.com/diatoms.htm
about the causes of not controlled diatoms growth in aquarium
[...] excess nutrients, silicate and silicic acid are the ingredients for a diatom bloom. Silicic acid enters the aquarium by using tap water;
substrate can contain silicates that leach out over time. RO/DI units can filter silicic acid out, but only for a limited time. Eliminating silicates
can control diatoms. [...]
So, lots of silicates in our water to grow diatoms 
In attachment there is an extract from Brauer about the preparation of silicic acids. The main component for doing this seems to be sodium silicate.
This can be easily made from pieces of glass put in molten NaOH.
Any suggestion welcomed
[Edited on 10-6-2006 by kazaa81]
Attachment: Silicic Acids.txt (4kB)
This file has been downloaded 1281 times
lordmagnus - 10-6-2006 at 19:50
Yes, you will need a fair ammount of sillicate for the diatoms to build their shells out of.
kazaa81 - 11-6-2006 at 04:58
So, a dilute solution of sodium metasilicate (water glass) is enough? Or do I need to convert it to a silicic acid?
Also, can sodium silicate synthetized from molten NaOH and glass be suitable for the purpose of growing diatoms?
Sodium Metasilicate
Na2SiO3
CAS #: 6834-92-0
Mol. 122,064 g/mol
Form: white amorphous solid; hygroscopic
M.P. 1089°C
Density 2,61 g/cm^3
Soluble in cold H2O; reacts in hot H2O
(data from CRC handbook of chemistry and physics 85th edition)
Thanks all for help
kazaa81 - 15-6-2006 at 02:20
Tips on growing and controlling diatoms in an aquarium
http://www.advancedaquarist.com/2005/5/tips
gil - 3-12-2006 at 15:16
what tips do you need! Just look closer/better!