Clarkii Larval Rearing (no rotifers?)

[jwreffner]

Not that I'm an expert or anything, but if a rot gets in your algae cultures, you could lose your cultures. If I were you, I'd seperate them a bit. It would really suck if you lost your algae.

Jay

[jnowell]

I hear ya' Jay, I had thought about that. I plan to go buy another 25ft. of airline, and another gang valve so I can move the algae cultures to the top of the shelves you see in the room pic. Got a Christmas party to attend tonight, so the move is first on the list for tomorrow....good advice!

As a "just in case", I had a friend of mine start cultures at his place simultaneously, he doesn't have rotifers yet, so I'm (sort of) safe for now. His clowns haven't laid eggs yet, but he's getting ready just in case. I'll probably give him a batch of mine if his don't get with the program. We bought them within a few days of each other, but you know how it goes. I know for a fact that the fish never work on your schedule.

Jason

[jnowell]

Well, so much for the single 15w PC idea, the fish didn't seem to mind it, but the temp went up a full degree in just over an hour. I guess I could put a $15 cooling fan in my $10 hood...nah. The fry come right to the top when I remove the hood with just the kitchen lights on, I think I'll stick to that.

I did notice that about 7 or so of the small, thin fry have died. I syphoned them off the bottom before they could decompose much. I hope that doesn't become a trend.

Jason

[Worldwithin]

It is interesting that you state that your rotifer density is only 5-7 or so per mil. Mine is currently well over that when I mix up the tank as they tend to cling to the walls and bottom. I would have to say that the average I get in my tanks is 50 - 100 easy (if not more) as I have never counted. I will admit that I feel that I have a dense culture for my needs.

Here is my setup


It is total DIY toss it together, but it is effective. Baically, it is a 5 gallon tank with a heater set to just shy of 70 degrees, an air bar under the heater to circulate the water and the continous drip being fed off a 1 liter soda bottle with my IA mixture in it. I also have a piece of floss inside the tank sitting on the bottom to collect whatever debris that settle on it. I trade this out every day or so with a second piece of floss to hopefully reduce the amount of debris from decaying in the tank. Luckily the rotifers pass through it for the most part so I am not loosing a large number of them to the floss change.

Anyhow, since the algae I put in there is not living, I see no need to put light over the tank. Rotifers themselves don't really care about light from my understanding, and also it is possible to introduce a bacteria bloom within the tank with light. Obviously if you are putting living algae in there, give it some light.

I just drained a gallon out of my tank, and in the filter sieve, I took a concentrated drop and looked at it under a microscope at 160x. There were at least 20 or so living rotifers in portion of the drop that I could see (far less than a ML) so I would assume that my density is rather high. It is difficult to calculate given the volume that I removed and the size of the drop... etc....

I would give the larger tank a go rather than the 2 liter bottles. And definately keep them either below your green water cultures, or completely away from them. While they may not crash a green water culture, they definately could turn it into a rotifer culture rather quickly.

If you are looking for some additional information that may help, check www.rotifer.com. They have some helpful tips that worked for me.

[Kathy55g]

2.5 drops is about 0.1 ml, 5 drops is about 0.2 ml. Count the rots from your culture in 5 drops of unfiltered culture, and then multiply by 5, and you will have the # of rots per ml in your culture. 20 rots in 5 drops is 100 rots per ml.

[Worldwithin]

Cool... Thanks Kmleah

[jnowell]

Thanks Leah, using your method, my batch cultures that I am feeding from are approximately 30 rotifers per mil (and I had just fed the fry). The fry look much more lively this morning, but I lost six more of the small, thin ones last night. It's the start of day 3, and I have about 40 healthy, and 5 thin fry left.

WW, my comment was that with only two dense batch cultures, I could only afford enough rotifers to STOCK the continuous culture tank to about 5 per mil. I'm using live microalgae and roto-rich, so I bet it's density increases rather rapidly. I just started it last night, that's the reason the density is so low in it right now. if it never gets above 5-7, I'll be very worried

Hey Leah, can you have too much light on a microalgae culture? I'm moving them to higher ground (away from the rotifers) this morning, and i have a spare 24" Orbit 2x65w power compact hood. I was thinking of using that for the light source, would that be acceptable? I have another 48" shop light also, but the shelves are only 36". Would the Orbit be better or worse.

Thanks for the help,

Jason

[Kathy55g]

I don't know. Intensity does not SEEM to matter, as NO shop lights work well. I have daylight bulbs on my shop lights. I do think 8 hours of off time is important, as plants have to rest too.

When counting rots, I have found that it is best to count several 5 drop pools and average the numbers, as the rots are not always evenly distributed in the tank.

Here's an old picture of my phyto culture shelves. The shelves were about 10$ each at wallyworld, and work very nicely with the shop lights just sitting across the back. I've now added a second shop light on the middle shelves so I can grow extra phyto for my reef club.



Hope to help,
Kathy

[Kathy55g]

I was doing rotifers on the bottom shelf, but I moved them to a place near the sink to get them away from the phyto.

[Kathy55g]

At 30 rots per ml, be careful not to overfeed. Better to feed more frequently, but feed less.

[jnowell]

Maybe a trip to Wal-Mart is in order, I like the shelf setup from your pic. I'm using NO "grow lights" in my shop light, and they are working fine. My second shop light came with bulbs, so maybe I'll just use that on some new shelves.

Overfeeding my rotifer culture is a big concern of mine too, but so is underfeeding them, cause I need them to grow and grow quick! I keep the water moderately cloudy with Roto-Rich, and it starts to clear within about 8 hours. I always feed a small amount before it gets too clear. One of the cultures does have some green clumpy stuff on the sides near the bottom. I fed from that one today and siphone about 3/4 of the water out and replaced with new water. The two new cultures that I started yesterday afternoon are starting to show good density increase, so I think I will be OK. Now that I've got 5 batchs and one continuous going, I feel a little more relaxed.

The one dense batch that I didn't feed out of today is at 50 per mil, so they appear to be re-populating faster than I am harvesting, but I won't know that for sure until I check them a few more times over the next few days.

Thanks for the help, Kathy (your screen name fooled me, I won't call you leah anymore )

Jason

[jnowell]

Just for grins, here are the parents. The male is already cleaning the rock where they laid the first batch of eggs...but only when the female tells him to. Some things are the same no matter what species you are.

[jnowell]

While I'm being photo-happy, is this normal behavior?? About 15 of the fry are right up against the glass, head first, just sitting there, they move occasionally, but just hang out there most of the time.

[Worldwithin]

Originally posted by jnowell
WW, my comment was that with only two dense batch cultures, I could only afford enough rotifers to STOCK the continuous culture tank to about 5 per mil. I'm using live microalgae and roto-rich, so I bet it's density increases rather rapidly. I just started it last night, that's the reason the density is so low in it right now. if it never gets above 5-7, I'll be very worried

Ahhhhh... I see..



As for the fry sitting at the top of the tank, I didn't really have any issues with those that did that as they seemed to be feeding off the rots that decided the surface was a good place to swim around.

In regards to the rots multiplying faster than you can harvest them... Harvest more of them, but feed them to your main tank. I started doing that just to keep the roti population in check, and noticed that a lot more stuff came out to feed on the plankton bits. Feathers, my chromis, and some of the smaller fish went nuts. You will find that once you balance everything out to your care schedule, your rots could easily double their population in one day. I actually harvest at least 25% per day... Sometimes up to 50%. This current batch has been up and running for about 3 weeks now with no noticable issues in either population growth, or density. So far, so good. (fingers crossed).

Oh, and I did a quick count on my culture... I am currently hitting about 120 per mil. Not huge, but fully sufficient for my needs.

[jnowell]

I'm looking forward to when my population hits those kind of numbers. About 3 days before my eggs were due to hatch, I gave up on the "no live food" method, and ordered 2 quarts of live rotifers from FAF. Since then, it's been a balancing act trying to keep densities high enough for the fry, without depleting the cultures from the original 2 quarts.

I'm not going to harvest the continuous culture until it hits good population, that way I'll at least be ready for the next hatch. If I get a few to survive this go around, I'll consider myself lucky.

There are about 10 of them that are larger and darker colored than the rest. Their stomachs have also turned more silver grey, so at least some of them are happy and healthy so far.

As for a grow out tank (post metamorphasis), would my 58 gallon coral propagation tank be alright? I certainly don't want to crash it, because I have some awesome bright orange Zoanthids that are spreading to everything in there. I have minimal filtration on it right now, but have fired up my Magnum 350 canister on the display to cycle some bio media, anyone think the magnum could keep up with the bio load of growing clowns?

Thanks for the tips!

[Worldwithin]

It is hard to say if I would suggest putting them into your grow out tank. They will still be extremely small in size, and can easily get lost in the tank. Also, considering you need to keep the food density high enough for them to find, you may run into a nutrient issue in that tank. The Mag 350 will most likely suck them up if they get anywhere near the intake.

I totally undsertand waiting to harvest your continous culture... I would still harvest some of them, but not anything like 50%. This will still allow room for increased density, but also give you some extra food.

[jnowell]

OK, so I left the house at 7:00 and all was well, when I returned at 11:30, one of my microalgae cultures had completely crashed. It was mostly clear, and all the algae was clumped together at the bottom. I assume this was a bacterial infection? They were all started from the exact same water, 3 are fine, one is gone (all have filter floss covering the opening). I stirred it up to see if maybe it could be recovered, but I don't think so. The others look smooth, kinda like antifreeze, this one is very granular and a duller green.

At first I thought maybe it was a rotifer contamination, because there were tiny particles floating around in the clear water that resembled rots. Under a loupe, it just appears to be small chunks of algae still suspended in the water. The air was still running when I came in, I just shut it off to see if there might be rotifers in it. I'll check it again in the morning.

Here's a pic...any guesses?

[Worldwithin]

I ran across what causes that somewhere, but just cannot remember where I found it.... If I recall, I think it has crashed. If I manage to find it again, I will post it unless someone else beats me to it.

I don't think that rotifers are causing the problem.. If it was a rotifer infestation, they would just eat the algae and multiply until you got a rotifer colony instead of an algae colony.

Give this thread a shot to see if it is in there somewhere:
http://archive.reefcentral.com/forum...hreadid=638436

I think I ran across something similar to that in there, or it was in a book somewhere... Regardless, I am sure that someone has an answer for that one.

[Kathy55g]

Looks bacterial to me.

Do you bleach or otherwise sterilize your water and bottles before you use them? This would prevent such crashes, and works great for me.
Kathy (I would like to change that screen name, but the powers that be haven't answered my email)

[jnowell]

Actually, I just rinsed the bottles out with tap water, and let them dry upside down....THEN I read about adding some bleach, rinsing and adding de-chlor. As I restart the cultures, I'll be sure to use bleach. This was but one of the many pitfalls of trying to hack this together at the last minute. I am learning a lot though, thanks in a large part to my new hero's on this board

On a good note, I had great rotifer density this morning, and finally feel like I got the rearing tank up to the correct density with my feed this morning. Lost another 4 fry last night, but so far, it's always been the little thin ones (except the tranfer damaged casualty, he was healthy). That's just about all of the smaller ones, so now I've past day 3 with about 35 apparently healthy babies.

Now on to day 8 where I can kill more of them with BBS, time to practice my decapsilating skills.

[seafarm]

Regardless of your current density it is important to harvest your rotifers daily. Rotifers will live for 10-12 days but only produce eggs for 2-3 days so if your population gets old, your culture stops reproducing. Then you have your larger, older rotifers eating all your food, but not making any eggs. This is why batch systems crash after 7-10 days - the population of young fecund females drops to almost nothing.

We produce roughly 500 million rotifers each day and recommend harvesting a minimum of 33% of your culture every day. This statistically wipes out your older females, leaving just the young ones.

Our culture system has been running continuously for over 2 years at a standard density of 2500 - 5000 per ml (peak was 10,000 / ml) and we harvest 50-80% of our culture every day.

It seems counter intuitive, but to get your densities up - you have to harvest.

[jnowell]

Thanks Randy, that makes a lot of sense. I had ordered the live culture from Florida Aqua Farms, they spent two days in shipping, and I stocked the rearing tank, and two cultures from the order. I tried NOT to harvest for the first few days to get the densities up, with no progress. It finally became nessecary to re-stock the rearing tank, so I harvested 50% of the two batch cultures, 2 days later I had booming (by my standards) populations in each. Now that the populations are up, I havest 30-50% of one each morning, and the other each evening. Since I began this regimen the densities are increasing exponentially. It all seems so clear now

Any comments from a seasoned veteran like yourself on feeding the rotifers? I've been alternating between Roto-Rich and fresh grown Nanno Cl. They seem to eat the microalgae faster than the mix, and the extreme nutrients in the mix worries me when used for a dense continous culture.

Once my 10 gallon continous culture matures (with harvesting now), I'm planning to pull some out into another container, and give them the mix for 3 hours before feeding them to the fry. Am I on the right track? Nice sites by the way, I bet you get some business from me before I get through this

Thanks again,

Jason

[jnowell]

Randy,

Disregard the last set of questions. 20 minutes reading your web site answered all my questions (go figure). And you already have the aforementioned order Who says internet marketing doesn't work, and you didn't even have to spam me

J

[seafarm]

Hi Jason,

I'm glad our website was helpful. If you want to see some cool pictures of rotifers @ 7,000 ml check out http://www.rotifer.com/icrs2/pictures.htm. These pictures are several years old and not our current system, but still interesting.

As a microalgae producer I'm clearly biased towards algal feeds instead of yeast based feeds. Yeast based feeds are less expensive but more prone to crashing because they stimulate faster bacteria growth, and they require a lot more cleaning. But that's a much bigger concern in commercial hatcheries than in home setups.

[Armando]

Randy,

How do I harvest the culture in a way that I catch the older females and leave the young ones? Would the use of a 53u sieve do the trick? (assuming younger females would be smaller than 53u?)