Nourishing Your Marines: Foods/Feeding/Nutrition by Bob Fenner

As “worlds of our creation” marine aquariums are reliant on us for adequate inputs of food, in acceptable formats, that provide sufficient nutrients for growth and maintenance of  all our livestock. Nourishing marines is a twin-edged sword however; a balance between adding needed materials while trying to avoid polluting the system. There are a few approaches to nourishing marine livestock and more than a handful of caveats to consider in preventing self-induced maintenance problems from over- and mis-feeding.

 

·         Goals: Are you feeding for growth or maintenance? This is an important question on a few counts. Of a certainty, marine life that is fed minimally is longer-lived and less trouble to maintain. There is less waste and its effects, like increased algae growth, to contend with, less aggression amongst tankmates of differential growth rates, and it’s a proven fact that lean specimens have longer life spans.

On the other hand, most aquarists want to see their specimens grow larger, maybe even reproduce. This goal calls for more and often different foodstuffs, offered more frequently, sometimes in varying formats from simpler maintenance regimens.

 

·         Foods: Come in many shapes, sizes and make-ups, and these variations are important to their intended consumers. Dried-prepared flakes, pellets, crisps, freeze-dried, frozen, fresh and more formats are available as store bought and some human-consumption rated foods. Which are best? That depends on the species in question and your set-up.

 

·         Feeding: Simply plopping in a portion of nutritional value into the water oh so often is not the end all to nourishing your marines. They, your livestock, must take in the offered foods. Just as with ourselves, fishes and invertebrates have preferences for what types, sizes and formats of foods they’re presented, as well as how much, where, when and how often. Generalizations are difficult here, but you should think deeply about this. For each of the types of life in your system, when do they feed? Where? On what? Will it be necessary to place some foods near the surface, others at the bottom, as for moray eels? How often is often enough? Fancy Basses, Mandarin Gobies, Tangs and many others prefer an almost continual offering of food to stay happy. Live rock, a food-growing refugium, formulated time-release foods may be necessary for some of your captive marines. Larger, predatory fishes like Lionfishes, Groupers and Sharks do better being fed only every few days.

 

·         Nutrition: Not surprisingly, most marines have similar nutritional requirements as ourselves. The same mix of amino acids (the building blocks of proteins), fats, vitamins, minerals and water. Additionally, biomineralizing forms like clams and hermatypic corals require added amounts of alkaline earth elements (calcium, strontium, magnesium), especially in “boosted” environmental conditions. Much is known regarding the nutritional requirements of captive marines, and many commercial food lines are on the market that can provide complete nutrition. Your task, as aquarist-creator is to investigate what’s needed and available and apply these foods. As an example, bio-minerals can be administered as additives, via a “calcium” reactor, the use of live rock/live sand, and/or feeding.  Which is better/best? This depends on your individual livestock, your set-up and goals.

 

·         Variety: Is indeed “the spice of life”. As with companion animals and ourselves your marine livestock benefit from a mix of different foods in two ways; enhanced interest and filling in needed nutrients. Yes, even fishes get bored with the same old foods. They “brighten up” color and behavior-wise with offerings of different formats (fresh let’s say versus dried, and vice versa), even different brands. What’s more, “something” missing in one prepared diet or foodstuff is often “made-up” in another. Nutritional insufficiencies can be avoided by supplementation as well, by treating foods with vitamin and appetite stimulant preparations ahead of their offering.

 

·         Balance: Moderation in all things encompasses our roles as aquarists. A balance will be struck between what you feed, how you feed it, and how it is accepted and processed by your SYSTEM. Note that last word. You’re “feeding” your entire tank when you place food and supplements into it, not just the livestock. What’s the sense of going to all the trouble and expense of proper set-up, careful water preparation, filtration and other maintenance without understanding the roles and ultimate disposition of the foods you pour in?

Think about this. Just as certain as your filtration, circulation and overall dilution can handle so much waste and uneaten food, so certainly will noisome algae proliferate to help you take up the excess. Therefore it is important to provide foods that are as nutritious and palatable as possible and make sure they get into your livestock.

 

Nourishing your marine system presents challenges and opportunities that can make or break the balance of  your goals as a marine keeper with that of your set-up and livestocks capacity for growth, maintenance and stability. It is up to you to know your specific livestocks nutritional requirements and meet them with foods of acceptable formats, in desireable shapes and sizes, at the right frequency. The “answer” to how much, how often of what is a matter of study, your set-ups specifications, your goals, and above all, your careful observation of your livestock. Feeding times offer the best chance of telling whether all your marines are being nutrified.