Why Live Food?

Introduction

Why do I rely on Live Food for my Marine Aquarium inhabitants? "Spike", shown in the top photo, was 5-years old in November 2009 and his diet is almost exclusively Live Brine Shrimp.

"Herkimer", shown in the bottom photo was 7-years old when he jumped out of the tank (fatal move) when no-one was around and he had just completed a air-freight trip from New Jersey to Florida. As in the case of Herkimer, Spike's color, health and longevity is the result of an almost exclusive diet of Live Brine Shrimp. Not just any brine shrimp but enriched live brine shrimp from Northeast Brineshrimp (Live BrineShrimp.com).

Northeast Brineshrimp (LiveBrineShrimp.com) uses a Beta-Meal supplement to produce enhanced Brine Shrimp so your captive fish and invertebrates have the benefit of natural color as well as improved health and vitality.

So why do the Public Aquarium professionals and LiveBrineShrimp.com customers rely on Live Food? A number of reasons come to mind:

1. Some Specimens will only eat Live Food.

2. Feeding time is more of an event for all concerned.

3. Health and Nutrition.

Health and Nutrition

I spend a part of my summers in Northern Greece and am impressed with the amount of Farmed Fish that I see in the market (Grrece produces 242 million pound of farmed fish annually). The photo shows a small fish farm on the coast of Sithonia in the Halkidiki. For Sea Bream and Sea Bass, the Government Research facilities in Athens reported (ref 4 in the following Table) that the most satisfactory diet for these marine fish consists of 55% protein and 12% lipids.
Notice in Table 1 the similarity with the nutritional values for Adult Live Brine Shrimp (Artemia) and also how close the U.S. Commercial feeds (Starter Feeds) approximate Live Adult Brine Shrimp. The fact is that Herkimer (Reef Butterfly) and Spike (Blue Damsel), from the previos section, were well fed on their diet of adult live brine shrimp. And they vigorously feasted at feeding time.

Table 1
Fish Feed Nutrition

 
Protein, %
Lipid, %
Ref
       
Live Brine Shrimp
(1)
Adult
56.4
11.8
Nauplii
52.2
18.9
 
Live Rotifers
55.5
<13
(2)
 
Commercial Marine Foods
(3)
"FinFish Starter"
50.0
15.0
"Marine Starter"
50.0
14.0
 
FAO, Greece Marine Diet
55.0
12.0
(4)
 
Frozen Foods
(5)
Brine Shrimp
60.6
9.1
Cyclops
82.5
10.0
Mysid Shrimp
65.8
7.2
 
Dried Tropical Flakes
50.0
10.6
(5)
       
1.
"The nutritional value of Artemia: a review", 1987 Vol. 3, P.Sorgeloos, D.A.Bengtson, W.Declier, and E.Jaspers. Universa Press, Wetteren, Belgium
2.
MBL Aquaculture (Southern Regional Aquaculture Center), October 2000, Pechmanee and Assavaare.
3.
Commercial Feed Labels
4.
FAO "Fish Feed Technology and Fish Nutrition, Greece" (1987) Allen J. Matty
5.
Doctors Foster and Smith Online Catalog, December 2009

 

Larval fish and pre-adult invertibrates require a higher lipid content with the higher total calories that results during these early growth stages. The Nauplii stage of Brine Shrimp contains 18.9 % lipid making it the choice for larval fish cultures since the 1930's. Live rotifers have a role to play as well where their size matches the capability of the feeder and the nutrition (lipid) level appears close enough. in 1971, McMaster (CEO of Northeast Brineshrimp) published an evaluation of Rotifers as a food for larval anchovies. I would suggest that the ideal nutrition level for larval fish approaches that of fish roe which is 20% lipid and 69% protein.

The Freezing and Drying processes lead to cell disruption, lipid and water loss, and lipid oxidation (drying). The lower lipid content of these products (frozen foods and dried foods) is reflected in their lower lipid percentages. As you may be familiar from nutrition labels you see every day, lipids have more than twice as many calories as proteins or as carbohydrates (9 kcalories per gram compared to 4 kcalories per gram). Few restrict the calorie intact of their aquarium pets and no one recommends restricting such with baby/infant critters.

Processed foods, including frozen foods, rely on "enrichment" with vitamin and fatty acid supplements that boost the overall product assays. Provided that the supplement can be utilized by the critter, there can be value in such enrichment. There is probably no value to mineral oil added as a processing aid in dried and pelleted feeds (higher lipids reported). There is harm associated with the recent Chinese fraud of adding melamine to raise the protein assay. Supplements that immediately leach into the aquarium water, are not available to the aquarium inhabitant and are therefore completely wasted, except to enhance the product label.

Food enhancement and use of vitamin and fatty acid supplements can be very valuble to the aquarium owner if done correctly. To be efficatious, the supplements need to be incorporated into the body of the live (or previously live) food. This practice of "gut-loading" will be discussed in the next installment of "Why Live Foods".