Algae for fish food - Aquaponic Gardening2024-03-28T10:30:16Zhttps://aquaponicgardening.ning.com/forum/topics/algae-for-fish-food?feed=yes&xn_auth=noDid you ever do this?tag:aquaponicgardening.ning.com,2022-02-14:4778851:Comment:7165012022-02-14T00:01:40.477ZSteven Archambaulthttps://aquaponicgardening.ning.com/profile/StevenArchambault
<p>Did you ever do this?</p>
<p>Did you ever do this?</p> It is great that you are thin…tag:aquaponicgardening.ning.com,2016-02-10:4778851:Comment:6237652016-02-10T22:09:12.575ZJohn Stevensonhttps://aquaponicgardening.ning.com/profile/JohnStevenson
<p>It is great that you are thinking in terms of replicating nature and using the free energy of the sun to create fish food. Algae and the planktonic crustaceans it feeds is an important part of the life cycle. But, I would say it is a building block not the solution.</p>
<p>I have experimented with algae and Tilapia and my results showed only a subsistence level of growth. To be fair, I am not sure if there is a threshold of how much Algae a Tilapia can take in or if I just did not have…</p>
<p>It is great that you are thinking in terms of replicating nature and using the free energy of the sun to create fish food. Algae and the planktonic crustaceans it feeds is an important part of the life cycle. But, I would say it is a building block not the solution.</p>
<p>I have experimented with algae and Tilapia and my results showed only a subsistence level of growth. To be fair, I am not sure if there is a threshold of how much Algae a Tilapia can take in or if I just did not have enough life growing in the tank. Based on Nate’s numbers above, I am assuming the latter. If I decide to give it another go I would culture entirely outside of the system to better record the feeding and for faster production. I was also considering building a Rotifer production system for giggles.</p>
<p>Algae is great but why monoculture? In the food chain there are many organisms that feed on algae. The fish feed on these organisms, so why not diversify their diet by creating several mini ecosystems with varying foods. It sounds like you have a bit of that going on already in your shallow media beds. I am a big fan of (Scuds) Amphipoda and the fish love them. These small organisms feed small fish and big fish eat small fish. I would not force a cannibalistic feed on my fish. I am however feeding Tilapia fry, runts, and fingerlings to Yellow Perch and Walleye. Once I have a decent population of these, they will return the favor and feed the Tilapia.</p>
<p>The sun makes the algae. The fry and young fish feed on the algae. Small fish are fed to big fish. Fish feed net cost zero. Well…to be fair, I cultivate insects, worms, and plants as well. They are used for supplemental feeding and to vary the diet. Energy costs are also a concern. I am beginning to monitor them with a sub meter. I am in the process of putting together a list of the plants and animals and the methods I employ to culture them. I plan to post it here when completed.</p>
<p>If you are raising Tilapia, you may want to consider live bearing aquarium fish like guppies, mollies, etc. They reproduce easily and will feed on the algae and the associated life it supports. The offspring make great fish food and I can’t help but speculate that it would be healthier for the fish than a pure algae diet. </p>
<p>I would suggest you keep the algae you grow for human consumption separated from your aquaponics system. Spirulina can be infected by toxic algae so you should test it regularly to make sure it is safe. A smaller batch is easier to monitor and test than an entire system. You can also more easily regulate light, temperature, and ph to optimize growth in a smaller space.</p>
<p>I am very interested in your project and would love to hear about all your successes. Thank you for sharing.</p>
<p></p> This doesn't sound like a goo…tag:aquaponicgardening.ning.com,2016-01-28:4778851:Comment:6226402016-01-28T13:32:24.212Zpaul burtonhttps://aquaponicgardening.ning.com/profile/paulburton
This doesn't sound like a good idea tbh. The algae is consuming nutrients your plants could use.<br />
Do you use a sump tank or filter system.? Put some water fleas in there, they will eat the algae.<br />
And any that reach the fish tank. The fish will eat. Grow duck weed in a separate system I.E. tubs, bucket, ponds, ETC. Use that as fish food.
This doesn't sound like a good idea tbh. The algae is consuming nutrients your plants could use.<br />
Do you use a sump tank or filter system.? Put some water fleas in there, they will eat the algae.<br />
And any that reach the fish tank. The fish will eat. Grow duck weed in a separate system I.E. tubs, bucket, ponds, ETC. Use that as fish food. Sounds good. Let me know how…tag:aquaponicgardening.ning.com,2016-01-27:4778851:Comment:6225392016-01-27T14:51:47.689ZNate Storeyhttps://aquaponicgardening.ning.com/profile/NateStorey
<p>Sounds good. Let me know how it goes!</p>
<p>Sounds good. Let me know how it goes!</p> Thanks for the response Nate,…tag:aquaponicgardening.ning.com,2016-01-26:4778851:Comment:6227012016-01-26T21:48:16.949ZSacred Valleyhttps://aquaponicgardening.ning.com/profile/SacredValley
<p>Thanks for the response Nate, your awesome.</p>
<p>I am finding that spirulina is 60% protein (high), 24% carb, 8% fat and packed with Vitamin and Minerals. With a break down like that, would the feed reqs be reduced? Also do you see a discrepancy with the FCR being based on dry weight of highly processed feeds, this compared to a wet and living food source, one that tilapia are perfectly adapted (practically engineered) to eat? Still i think an obstacle or daily hazard would be harvesting…</p>
<p>Thanks for the response Nate, your awesome.</p>
<p>I am finding that spirulina is 60% protein (high), 24% carb, 8% fat and packed with Vitamin and Minerals. With a break down like that, would the feed reqs be reduced? Also do you see a discrepancy with the FCR being based on dry weight of highly processed feeds, this compared to a wet and living food source, one that tilapia are perfectly adapted (practically engineered) to eat? Still i think an obstacle or daily hazard would be harvesting or screening that much Algae, but with some screening techniques it could be simplified. <br/>
With 275 gallons of cultured algae (IBC not all the way full and 350 feet of clear thin wall PVC 2"), at 97% water , thats 8.25 gallons of concentrated, wet algae. I don't know how much that weighs, but a gallon of water weighs 8.34 pounds, that almost 69 pounds of concentrated wet algae. not too shabby...but thats for daily feed reqs...</p>
<p>I would also think that its worth its weight for fry and fingerling feed. Fry and Small fingerling are geared towards eating solely micro algaes and inverts in the wild.</p>
<p>I understand I will never achieve growth rates as found as standard in aquaculture, but definitely want to keep the conversation going about the potential of spirulina in a greenhouse. With the clear thin wall PVC getting more affordable, using the existing structure of a well built greenhouse seems like just another way for us to maximize space and yield. I Love consuming spirulina and I think its potential and power as a healthy food crop ( and possibly fuel crop) is fun to think about.</p>
<p>I going to start this project anyways so ill keep you all posted! Thanks again!</p>
<p>-justin</p> That's a tough one Justin, yo…tag:aquaponicgardening.ning.com,2016-01-26:4778851:Comment:6226102016-01-26T19:08:37.073ZNate Storeyhttps://aquaponicgardening.ning.com/profile/NateStorey
<p>That's a tough one Justin, your FCRs are typically based on dry weight of feed with high protein content. Cultured algae is typically 96-97% water and low protein, so with a great FCR of 1:1.6 you'd want a feed with a minimum of 35% protein at at least 1.5% of total fish biomass daily. So in this hypothetical situation for 100 lbs of fish, you'd need at least 1.5 lbs dry algae daily at 35% protein. Protein around 10-12% is more likely, so you'd need around 4.5 lbs total on a daily basis…</p>
<p>That's a tough one Justin, your FCRs are typically based on dry weight of feed with high protein content. Cultured algae is typically 96-97% water and low protein, so with a great FCR of 1:1.6 you'd want a feed with a minimum of 35% protein at at least 1.5% of total fish biomass daily. So in this hypothetical situation for 100 lbs of fish, you'd need at least 1.5 lbs dry algae daily at 35% protein. Protein around 10-12% is more likely, so you'd need around 4.5 lbs total on a daily basis for fish feed. This means you'd have to harvest 4.5/(100%-96%)= 112.5 lbs of algae (wet weight) daily. That's a lot of algae to replace fish feed. If you don't care about fish growth you can use less, but you will start running into nutrient deficiencies in both your plants and fish at that point. . . it just gets very complicated. Hope that's helpful!</p>
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<p>-Nate</p>