calling out to rotifer culturists

hello,

im a little concerned at the speed at wich my nanochloropsis is consumed by my rotifers in my 1 litre culturing vessels.

I have 7 jars, one for each day of the week. when I harvest I collect about three quarters of the jar and top off the rest with "green water". the jar gains a nice lively light green tint but goes clear in about 3-4 days (depending on the culture). I think the cultures still grow even if the water in the jar is clear but should I be concerned if the cultures go 3 or 4 days with clear water till next harvest?

clearly the easier solution would be to harvest and add more phytoplankton but if there is a simpler manner ill take it, not to mention I have two 2liters jars of green water and im barely managing with that (setting up a third jar soon)

Couple of pics







and for the record that "killers" in the back is a terrible vhs documentary on animal predators....before you go thinking something else

 

IMO, rotifers consume more nanno than my larger brine cultures.
Now though it doesn't matter as I use powdered spirulina, blended in water for at least two minutes and adding as required. In my 5g inverted water bottle cultures, I would add enough to get it fairly dark and once it clears, I add more, usually this means twice a day.
Just remember though that rotifers basically need to be enriched to be of much value, especially if you are using them for fry. The spirulina is of more nutrient value than the nanno, and then I enrich with Algamac 3050 (high in DHA) before using the rots.

 

ill take a look into liquid enrichments, but from what iv researched the rotifers obtain the needed fatty acids for healthy larvae growth already from a healthy diet of nanno. im guessing the rotifers lose nutritional value the more they stay in clear water?

 

urgh! sometimes all you got to do is re read an old article...

The Breeder's Net: The Rotifer And Rotifer Home Culture — Advanced Aquarist | Aquarist Magazine and Blog

 

do you currently have fry or are you waiting on another hatch? Would love to see pictures of the fry if you have them.

 

This is the nutrient profile for nanno: On average, the biomass contained 37.6% (w/w) available carbohydrates, 28.8% crude protein, and 18.4% total lipids. Mineral in 100 g of dry biomass were as follows: Ca (972 mg), K (533 mg), Na (659 mg), Mg (316 mg), Zn (103 mg), Fe (136 mg), Mn (3.4 mg), Cu (35.0 mg), Ni (0.22 mg), and Co (<0.1 mg). Toxic heavy metal contents (Cd and Pb) were negligible. Fatty acid content was as follows (on percent dry weight): 0.6% of 14:0, 5.0% of 16:0; 4.7% of 16:1omega7, 3.8% of 18:1omega9, 0.4% of 18:2omega6; 0.7% of 20:4omega6, and 2.2% of 20:5omega3.
While you can grow the rots with that, their profile will not be all that good without using tetra and iso along with it, especially for the DHA (part of omega 3).
You need other cultures to give a decent profile for enrichment factors.
For me, it became a PITA to keep them all going for the large quantities I was using, (150g constantly under culture for the nanno), so I switched to the excellent food spirolina and added the algamac for the DHA component.
While I have to clean the rotifer containers more often due to inert foods, it is still a lot less work than maintaining the live cultures.

 

thx for sharing your personal experiences ray, ill defenitly take a look into it this stuff. OFK I'm currently waiting for a new hatch, had one recently but i miss calculated the hatch night and was able to literally only catch one little guy, but didn't make it . I'm looking into over night fry traps…speaking of which here is a diagram with my idea, any suggestions are more than welcome.

the idea is to place a light near the mouth of the upside down half cut coke bottle. the bubbles produced in the hose by the airline should, in theory, suck and push the little larvae up the hose tube and into the funnel like part of the bottle….correct? the hose part inside the coke bottle will be just a little under the water line making it difficult for the larvae to escape through the same way they came in.



here is a picture of my little dude OFK




P.s im sorry if my awesome drawing skills made your eyes bleed

 

Well I've never considered trying to get a fry trap going.
For me, it's seahorse fry and they are usually born just before lights come on so I just get up early and catch them then.