alrighty... these cultures have been running for quite a while so dont be suprised by much of the missing info... I'll try and add as much as possible. Later on I may add in a primer on starting the cultures from agar media for those who are interested. First off... the basic culture rack construction
Important to note that in this picture you see the Co2 rig nearby, I am NOT using Co2 in my Nannochloropsis cultures.
A shot of a culture before being split --
For this split due to fouling of the original vessel I will be changing jugs... It's also important to note that I keep pre mixed ASW on hand at varying salinities in sealed jugs (which are rotated to zooplankton cultures if they foul or are contaminated, never re-used for algal cultures). I do NOT mix my gullards solution ahead of time, this has greatly helped avoid pre-contamination. A shot of the empty water jug and my ASW storage container:
I try to keep the distance between the petcock of the ASW jug and the bottle separated at least 3 inches when filling, this also helps to reduce contamination issues. When splitting into a new culture jar I will add the ASW first then decant the culture through a 250um sieve (to remove excess detritus) If maintaining the same vessel I will decant into a holding jug and then add the ASW to the original culture (no sieving).
Because of the nature of gullards (or any other nutrients for that matter) I like to store it in opaque containers to keep them out of the light. I managed to scrounge up a number of medicine containers that feature a nifty top that allows withdrawal of the fluid using a syringe (without needle). The syringes are graduated in g but the conversion is .5 gram / ml and makes for easy measurement... also once again helping to avoid contamination!! All medium is labeled and kept tightly capped, and the syringes are discarded any time they are dropped or any other contamination event occurs. After use the syringe is wiped with a kimwipe and placed in a ziplock bag.
(Important to note that I use these basic techniques with all of my algal cultures!)
Often during a split regardless of species some samples are decanted into a tray and pipetted out to a slide for examination. This helps me to identify possible contamination issues early on, as well as monitor the health of the algal cells. Most times density is quickly measured using a seechi stick but every few splits I like to do full counts with a Hemocytometer and reference back to make sure I am on track with density.
Apologies for the poor image quality, my camera and scope dont like each other. Note the lack of distinguishing features on the cells. good ole nanno
and here we are post split... note the lighter color... also note the cloudy appearance... this was a culture that I got lazy with and didnt sieve... I probably should have as this culture will be in danger of crashing later.
unrelated issue and a different culture (same species though) here is a crash I just happened to experience today!! one of the first in many months for me