Automated Rotifer Doser

[TheClark]

Interesting...

 

When reading this article on italian reef tanks:

 

https://reefbuilders.com/2016/11/19/reef-tanks-of-italy/

 

 

I ran across a tank that uses an automated rotifer doser.  

 

Planctondose

 

https://reefs.com/2014/09/29/planctontechs-new-planctondose-depth-review/

 

Anyone mess with rotifers around here?  

 

Anyone automate it?

[IntoTheMystic]

I and a colleague culture rotifers and other live foods on an ongoing basis at work and use them for feeding larval fishes, various temperate inverts and target feeding my corals. After a couple years of feeding experiments and occasional crashes of larval animals, I am very leery of holding live foods for any length of time and then feeding them out, particularly if it is feeding a closed tropical marine system.

 

Even under clean and controlled conditions with good biosecurity protocols, the same conditions that help rotifer, Artemia, and copepod cultures thrive also favor bacteria, especially Vibrio and other nasty little buggers. If you sieve and rinse the rotis and other foods well and then hold them and feed them out over time, you're dosing bacteria along with the rotis.

 

In theory, this could be a good way to slowly introduce food for various critters. Until recently, I had been planning to add a live food reservoir with a peristaltic pump on a timer to a temperate invert exhibit. In practice, however, this looks pretty risky to me.

 

My 0.02.

Edited November 20, 2016 by IntoTheMystic

[pledosophy]

Until recently, I had been planning to add a live food reservoir with a peristaltic pump on a timer to a temperate invert exhibit. In practice, however, this looks pretty risky to me.

 I have a setup similiar to this I have used. Basically a dorm fridge with an inline dosing pump. Worked alright for feeding phyto and powdered foods, but I never expanded it into rots or pods I was culturing. 

 

I agree on rotifers, IME they are to dirty of an animal.

I am curious if you have been able to culture specific species of vibrio from your rotifer and artemia cultures and what those strains have been?

[IntoTheMystic]

I haven't had the time or expertise or the lab tech to culture the specific strain of Vibrio but they do have a distinctive shape that is pretty easy to identify. Plus, these bacteria are distressingly common in brine cultures. I IDed the bacteria from skin scrapes on fresh larval morts. At the time, I was only feeding them 36-48 hour Artemia, which were added to the larval rearing tank a cup or two at a time from a holding vessel with an airstone. If ya wanna culture  bacteria that will wreck a lot of time and effort, this is the way to do it!

 

No mas.

 

Much better results these days without the bacteria incubator in the middle of the process. Just curious, what did the phyto and dried food do to your NO3 on that system and how did you address it?

Edited November 21, 2016 by IntoTheMystic

[pledosophy]

I haven't had the time or expertise or the lab tech to culture the specific strain of Vibrio but they do have a distinctive shape that is pretty easy to identify. Plus, these bacteria are distressingly common in brine cultures. I IDed the bacteria from skin scrapes on fresh larval morts. At the time, I was only feeding them 36-48 hour Artemia, which were added to the larval rearing tank a cup or two at a time from a holding vessel with an airstone. If ya wanna culture  bacteria that will wreck a lot of time and effort, this is the way to do it!

 

No mas.

 

Much better results these days without the bacteria incubator in the middle of the process. Just curious, what did the phyto and dried food do to your NO3 on that system and how did you address it?

I worked on theories behind the mixing species of Syngnathidaes for several years on the commercial side of the hobby. I had the help of a board certified pathologist, and all the equipment that came with it. He was able to perform necropsies on hundreds of animals and culture out many specific species of the bacteria. We also performed tests on those bacteria and how they performed under certain conditions. 

 

I am kicking myself that I never thought to explore the food source, but our research did not show a difference in WC or CB specimens. 

 

Our train of thought was that the Syngnathidaes were asymptomatic carriers of the bacteria and at increased temperatures certain strains became more virulent. For us 73F was a magic number. At 74F the bacteria would change its structure and become much more aggressive. Any previous immunity was no longer applicable to the change in structure. 

 

I am really curious about those bacteria being present in the food source and still being problematic at the lower temperatures of a temperate system.

 

As for the automatic feeder tests, I tried feeding at very small doses for non photosynthetic corals. My goal was to keep a constant supply of food for them to eat. My Nitrates were taken care of with carbon dosing and a taxifloria refugium. I am a huge fan of carbon dosing since I came onto it about 10 years ago. I have tried sugar and vinegar but I find Vokda to work the best. A peristaltic pump in small doses works much better for me than 1 large dose a day. On my reef tank now I am dosing 1mL ever 3 hours. So about an ounce a week, and it is working great. When I was doing the auto feeding of live phyto and dry food I was using 2 sugar packets a day. 

 

My system for the non photosynthetic tank was 1g of display for every 3 gallons of refugium. Small sump with a protein skimmer rated for the system size. I was having very promising results but had to tear it down after some severe medical problems. I think about trying a non photo tank again about 4-5 times a week. Still have that fridge... the problem now is sourcing the specimens. 

 

Side Note- I am really happy you are participating here. There are not a lot of people with your experience that still frequent forums. Thank you. 

[IntoTheMystic]

I am really curious about those bacteria being present in the food source and still being problematic at the lower temperatures of a temperate system.

 

 

Thanks for the kind words and you are very welcome. I'm planning on lurking less and contributing more in the days ahead. Your thoughts on temperature and pathogenicity are consistent with those of an experienced Syngnathid keeper I know, who came to the same conclusions.

 

Even after rinsing, there were enough bacteria in the Artemia to quickly repopulate when held at room temps around 65-68 degrees. I believe the problems of feeding this out to larval animals in open systems ranging from 50-58 degrees were manifold:

 

1. Volume of contaminated food. With each feeding, we were feeding ever-increasing amounts of bacteria, along with the brine. There were predictable losses here and there but eventually, we would see substantial die-offs. Can't believe it took me as long as it did to figure this out but this is how we learn. Around HMSC, we like to say, "debrief, don't second-guess."

 

2. Feeding only one variety of food. We all have to live under the tyranny of budgets and there simply wasn't the time or staffing to build additional culture-rearing infrastructure to raise more types of foods. We already cultured Artemia, so that's what we went with.

 

3. Husbandry logistics. We were/are working with larval Bay Pipefish, which are basically tiny 1/2"-long pieces of thread with fins right out of the hopper and stay small for months after. The detritus that comes in with the seawater collects on the bottom of the tank, along with waste and uneaten/dead food to create ideal conditions for a bacterial mat. The babies instinctively settle on the bottom of the tank at night, making it easy for bacteria to migrate onto them and overwhelm their immune systems. Making matters worse, siphoning this stuff must be done very carefully using a piece of rigid airline at the end of flexible airline. It's tedious, time-consuming and incredibly easy to overlook a baby and siphon it, along with the funk. Carefully removing the babies before cleaning the tank presents another problem: consider the size and fragility of the vertebrae on these critters. Even when being incredibly careful, handling them at all results in some of them getting bent at unnatural angles and their subsequent demise.

 

4. The accidental nature of the whole thing. When one of the males began giving birth, we decided to take a shot at raising them despite having no previous experience and little time or proper larval holding tanks. Despite the odds, one to three from each batch would make it to exhibit size, so every time a male would become gravid, we'd start the process again. The breakthrough came last summer, when we had the most successful culture yet, containing a few dozen 2-month old babies. We lost all but one in the span of one week, when we went back to the old way of doing things due to vacation coverage. Debrief, don't second-guess.

 

Now that we've completely threadjacked this guy's rotifer-dosing thread, how often did your pathologist find mycobacteria were the culprit in losses? In professional circles, it is generally assumed that Syngnathids are at least asymptomatic carriers.

[pledosophy]

Thanks for the kind words and you are very welcome. I'm planning on lurking less and contributing more in the days ahead. Your thoughts on temperature and pathogenicity are consistent with those of an experienced Syngnathid keeper I know, who came to the same conclusions.

 

I was breeding from 2001-2006. I didn't get to work with Marty much until 03-04 but the drop in temp is one of the things I attribute to being able to keep Reidi an Erectus for 6-8 years. IME dropping the temp for fry tanks helped out significantly which I started for metabolism and later thought, huh, I bet that works for the bacteria too. Most often with cases of vibriosis with other specimens I was able to cure with a reduced temp (65F for a tropical species like reidi or barbouri) and food supplements. 

 

I was helping with the disease forum on Seahorse.Org at the time and we would always see a huge uptick in bacterial infections over the summer months, so it started to kind of give us a hint something was up, but until Marty came around, we didn't have more than a suspicion. 

 

 

1. Volume of contaminated food. With each feeding, we were feeding ever-increasing amounts of bacteria, along with the brine. There were predictable losses here and there but eventually, we would see substantial die-offs. Can't believe it took me as long as it did to figure this out but this is how we learn. Around HMSC, we like to say, "debrief, don't second-guess.

 

Have you ever tried pro biotics in your cultures? I have a friend Dan who is doing so for his seahorse farm and he is having amazing luck with the species he is working with. 

 

2. Feeding only one variety of food. We all have to live under the tyranny of budgets and there simply wasn't the time or staffing to build additional culture-rearing infrastructure to raise more types of foods. We already cultured Artemia, so that's what we went with.

 

I hear that, my main hold back when I was breeding was the size of my kitchen and my girlfriend now wife, thinking we should be able to cook in it.

 

 

 . It's tedious, time-consuming and incredibly easy to overlook a baby and siphon it, along with the funk. Carefully removing the babies before cleaning the tank presents another problem: consider the size and fragility of the vertebrae on these critters. Even when being incredibly careful, handling them at all results in some of them getting bent at unnatural angles and their subsequent demise.

 

Been there done that LOL. I feel your pain. 

 

Now that we've completely threadjacked this guy's rotifer-dosing thread, how often did your pathologist find mycobacteria were the culprit in losses? In professional circles, it is generally assumed that Syngnathids are at least asymptomatic carriers

 

Myco was not often found. Very rare if I recall, I can only think of a handful of times. Where as erectus cultured out vibrio 60% of the time, Reidi was 70%, the other species were to small of a sample size for a determination. Some of the animals actually grew out  2 or 3 strains of vibrio. Of all of the samples vibrio was cultures in 71% of cases with 29% of the samples showing no growth. Specimens were taken by a pathologists who used salt supplementation in a Microscan Walkaway 40 at 35C for identification for species of vibrio for all o f the plates with distinct bacterial colony growth. 

 

What led us to the idea of a non symptomatic carrier state were that only a third or so of the specimens that  cultured positive actually died or showed signs/symptoms of vibrio. We had a hypothesis before based on a large number of hobbyists experiencing death of one or both seahorses after the introduction of a seahorse from a different source or a seahorse of a different species.