Spirulina as Fish Food; Fertilizers

 

This post is extracted from the Yahoo Groups: Spirulina-Group and is in the format of question and answers.

QUESTION:

I intend to recycle fish waste as nutrient to grow spirulina and in turns to feed the fish with the spirulina. I needed help on following: (Have read all previous messages but could not find the answer.)
•I culture tilapia in RAS (Recirculating Aquaculture Systems). Do I need to add other chemicals as nutrient. If yes, what are these and how much? I assume that I need to add calcium bicarbonate to increase the pH to 10. I should be using a 6m x 3m x 4m tank for the spirulina.
•How to determine sufficiency of these waste and chemical?
•Can I drip spirulina water into the fish tank directly allowing the fish to eat the fresh spirulina?
•Is there a problem if add the fish waste water directly to spirulina tank?
•How to get the spirulina seed?

Thank you.

---

ADVERTISEMENT:

---

ANSWER:

I think, you should add others chemical such as: NPK (Nitrogen/Phosphorus/Potassium)and TSP (Triple Superphosphate) fertilizer to grow spirulina faster beside bicarbonate.

Bicarbonate as a buffer I use to maintain the pH alteration. NPK and TSP are useful for macronutient of Spirulina growth.

I cultured Spirulina on fresh water with the main composition:
bicarbonate (NaHCO3) 10 grams per Liter
NPK 1-18 grams per Liter
TSP 1-2 grams per Liter

After cultivating about 14-28 days you can harvest it by nylon cloth.
Its better, rinse it with fresh and clean water to reduce some non organic material; 2-3 times, then you can add to the tilapia culture.

Spirulina is high protein content algae, so it's very good as a feed.

NPK RECIPIES, PRODUCTS

*Recipies:
*from How to Make a Complete Organic Fertilizer
•4 parts seed meal
•1 part dolomite lime
•½ part bone meal -or- 1 part soft rock phosphate
•½ part kelp meal

*homemade Fish/Seaweed Emulsion

*Products:
*All Natural Organic Fertilizer Concentrate, 3-1.5-2 NPK

A FEW SOURCES FOR NPK FERTILIZERS

Nitrogen Fertilizers:

*Potassium nitrate (13% N) is used as both a K source and a N source

*Ammonium nitrate (33% N) although a popular source in the past, it has storage problems associated with fire and explosive hazards (as well can raise be difficult to obtain due to "Red Flags" raised because of these hazards)

*Urea (46% N) is the most widely used dry N fertilizer. Once added, urea is converted to ammonia.

Phosphate Fertilizers:

*Diammonium phosphate (18-46-0) is a dry source of Phosphate. It has the advantage of being highly water soluble, having a high analysis and often a price advantage. Diammonium phosphate has an acid effect and thus buffers may need to be increased to maintain pH in Spirulina Cultures.

Potassium Fertilizers:

*Potassium Chloride (60 to 62% K2O), also referred to as muriate of potash. Excellent for use in blending of mixed fertilizers.

*Potassium nitrate (44% K2O), also known as nitrate of potash, this version of Potassium is generally not cost effective for many applications.

---

USEFUL RESOURCES:

*Purchase LED Lighting; an easy to understand article that frankly cuts through all the crap information surrounding LED Lighting for growing aquatic plants, corals.
*Are UV Sterilizers Good for an Aquarium?
*Aquarium LED Warranties; Reef or Planted
*St Marys College Biology LED Experiments

Freshwater Spirulina

Freshwater Spirulina (fusiformis)

This post is extracted from the Yahoo Groups: Spirulina-Group and is in the format of question and answers.

QUESTION:

I am looking for a fresh water Spirulina variant (Spirulina fusiformis). My aquaponics setup is strictly fresh water. I grow freshwater algae. I want to start growing Spirulina: Spirulina is the most balanced algae. I am trying to create a balanced algae diet for freshwater prawns, freshwater mussels, and fresh water tilappia. If there is not a freshwater Spirulina variant, then I need to find out how to incorporate the Spirulina into my system. I use the animal affluent to feed the algae. The algae filters, and cleans the affluent water. The cleaned water is then recycled back into the tanks. The animals eat the algae infused water. Right now, the alga is not a complete balanced algae feed. I would like to combine several algae and create a balanced live algae food.

I have seen on the internet that marine Spirulina contains much more nutrients than the fresh water variant. Is this true?

ANSWER:

To date there is no any variant of Spirulina which grows in fresh water or in neutral pH, all strains need the high pH and I think the high pH is not suitable for your aquaponics setup. You should grow the Spirulina in different tank (with correct chemistry, lighting, etc. for Spirulina growth) and then after harvesting, you can add it as a feed in the form of powder/ granules. Moreover, if you are looking for a fresh water nutritious algae then you can try the chlorella or nannochloropsis etc. green algae.
As well, there is not any significant variation in the marine and fresh water Spirulina strain.

"True" Spirulina needs such alkaline conditions other such aquatic life is inhibited. That is why it can be mass cultivated with minimal contamination.
Your best approach may be a polyculture of the afore mentioned chlorella, nannochloropis. Try adding also some nannochloris and diatoms, as many varieties as you can find. Without even trying you are likely going to get some other "wild" algae. Just watch out for potentially toxic algae which can easily foul your system.

Please see this article for further information about the use of Spirulina in aquariums/aquaculture:
Spirulina Algae; The Aquatic/Aquaculture Health Benefits for Tropical, Marine and Goldfish

Growing Spirulina Algae

Growing Spirulina can be really easy.
Start with the purchase of a live culture, then place it in sterilized creek, well, etc. water (freshwater) that had been altered by adding Sea salts, and PH brought up to a minimum of 8.4-8.8.
It is then placed it out doors. Night time temperature should not fall below
45F.

---

ADVERTISEMENT:

---

You have to adapt the culture first to salty sea water first if it was not used to it normally in the beginning medium. Adaptation needs some patience as well. You have to mix your culture with sea water slowly and every day with small amounts so that it can adapt easier. Sudden medium changes can result in osmotic shocks and the entire culture is dead. Divide the culture in different cups and make your trials separated and work on the method that works.


Spirulina cannot grow ONLY in seawater. It would also need soda ash, micro-nutrients, & bicarbonate to grow as well. The optimum ph is around 10 and the optimum temp is around 28-29 C (82-84 F). It is important that the equipment and the cups are free of other algae. The water should also be free of algae. You may boil the water before using as a practical way.

For more about Spirulina Algae’s health benefits for use in feeding both freshwater AND saltwater fish & invertebrates please see this excellent article:
Spirulina Algae; The aquatic health benefits for Tropical, Marine and Goldfish

Related Resources:

*Oregon Grape, Berberine for an Organic Aquarium Fish Treatment
*Economy Planted Aquarium LED; Fluval Aqualife & TMC AquaBar
*Chloroquine Phosphate, Quinine Hydrochloride-Sulfate for Aquarium