Saltcorner
By Bob Goemans
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Bob Goemans corresponds with David Novak (Austin TX.)

David Novak (Austin TX.) writes...

Dear Bob,

Let me start by saying I have been a reader of your articles from 1987. I have since gained a plethora of information and more importantly have watched the hobby grow scientifically to what now appears to be a full circle with a more holistic approach. Not just bludgeoning the marine aquarium into submission, but rather, scientifically understanding what is going on, i.e., the full understanding of completing the ammonia-nitrite-nitrate and even further into the cycle to remove nitrate via facultative anaerobes and the like to complete the cycle and control nitrates as well. A lot has changed in 14 years, but in a way Lee Chin Eng had grasped this concept way back when.

I guess there's more than one way to skin a cat, but I also believe there is only one best way to do it. I feel we are closing in on that with a fuller understanding of lighting needs, keeping water parameters up, what can be kept with what (or at all) and understanding animal husbandry, and that these creatures are dependant on us, just as your dog, cat or family for that matter. But on to my reason for writing - Over the years I have seen conflicting information concerning feeding land-based plant foods to fishes. I recall reading that land based vegetation has a different cell structure that is not readily broken down by their digestion system. Then, I have read of people feeding everything from lettuce to kale to broccoli to carrots to their fishes. Some people suggest freezing the foods before serving to break down the cell structure, others to cook or blanch them first, or use frozen foods, thawed from the box. Now as embarrassing as it is for me as a sport fisherman to admit, I have actually put Green Giant peas on a hook and you couldn't keep the opal eye perch off it with a stick so I know certain fish love their veggies! Of course, these fish were being caught to become part of 'my' food chain and the long term effects of them eating peas just wasn't going to be pondered upon. Now, I'm reading articles concerning Head & Lateral Line Syndrome being successfully treated with several foods from my grocers produce section. What's your opinion, as well as the scientific community's study of this?

I know most prepared fish foods have wheat flour and gluten in them (certainly from terra firma!), so it seems they can digest that ok. I have also caught fish in the wild that had Lateral Line problems and facial scarring. Nobody is keeping them from getting their veggies! I have a Lemonpeel angel that I have had for over 13 years. This fish has facial scarring that developed several years ago and has spread to cover its whole head, but not really affecting the Lateral Line. I also believe I have seen new scale growth on the head area in the past few years, which I attribute to feeding smaller quantities of my normal food selection, which does not consist of land-based plant foods. But I feed more often throughout the day because fishes normally forage and do not just sit down to three squares a day! However, if feeding my fish some cooked broccoli may induce more positive results in clearing up this scarring, guess I'll give it a go, but I won't if the long term result could be detrimental. This angelfish leads a normal happy active life with his few tank mates with plenty of space and doesn't seem physically bothered by his looks. It is a fish only tank and the nitrates while slightly high, are well within reason (lets say 35 ppm). But mainly my question is - Can fish break down these land veggies, digestively speaking or not? And, has anyone studied the long-term affects of this.

Looking forward to hearing from you, and keep up the good work! I believe Mother Nature appreciates you too!

David Novak

Austin TX.

Bob replies...

Hi David,

Thanks for your e-mail and agree that many now in the hobby are looking more towards science and trying to understand root cause instead of relying on superficial remedies. But we have a long way to go because some are difficult to convince and/or not wanting to change their ways. But those with an open mind will, in fact, are beginning to see how understanding nature's pathways result in better aquariums and healthier animals.

As for people foods, there's no doubt some of them have value for our finny friends. Poor diet can be the cause of many parasites and bacteria related problems. It can also cause the loss of what was a perfectly healthy fish. Once fishes become weakened by nutritional deficiencies they may never recover no matter what changes the aquarist makes to their diet. Underfeeding is a prevalent attitude among many aquarists as there is general fear of overfeeding the aquarium. I support not overfeeding, however, underfeeding is a totally separate subject. Some fishes are plankton feeders, some graze algae, some eat like cows and others eat only when an occasional meal is available.

It's therefore necessary to understand the number of feedings and type of food needed to provide long-term health. If numerous feedings are preferable, feed only what will be quickly eaten. The remark that "I only feed every other day" when there is a variety of plankton and algae grazers in the system is poor animal husbandry. Keep in mind the right type of foods fed the correct number of times each day helps maintain animal health for the long term. If water quality is a concern, there are ways to correct that without starving the fishes!

People foods, such as Romaine lettuce, Iceberg lettuce, kale, baby sweet peas, spinach and broccoli do not deliver the nutrients that fresh macroalgae or dried Nori seaweed can. However, these people foods continue to be used. Iceberg lettuce is not a fitting substitute for Romaine lettuce as it is very high in cellulose, which can clog the digestion tract. Neither is spinach, as it contains oxalic acid, which can cause crystals to form in the kidneys. In fact, most of these people green foods are high in nitrate, which will sooner or later show up in the aquarium.

Occasional feeding of these greens can add fiber to their diet and help keep their digestive tract clear. Yet there's really no worthwhile nutritional value for herbivorous animals with these people foods. For those who wish to continue using Iceberg or Romaine lettuce, first blanch it in scalding hot water for about 30 seconds or freeze it prior to feeding. You can also place them in a microwave for 15 seconds prior to feeding. This helps break down the cellulose and aids in digestion.

There are many different types of flake and freeze-dried foods. Most flake foods contain a variety of ingredients, e.g., algae, liver, Tubifex worms, shrimp meal, fish meal, yeast, and beef heart to mention just a few. The colors of the flakes are a fairly good nutritional indicator. Green flakes provide vegetable matter and enhance colors. Red flakes promote colors and encourage spawning. Yellow flakes provide growth and conditioning matter. Brown flakes provide natural raw material and enhance resistance to disease.

Spirulina flake is one of the more important flake foods, especially for herbivores. It is a microalgae and is specially grown for human consumption because it is high in protein and Beta Carotene plus many other vitamins and minerals. It's also a natural antibiotic and helps to improve survival rate. This green flake food is excellent for Surgeonfish, Angelfish and other species that require vegetable matter in their diets because its cell wall is a saccharate instead of a regular plant celluloid-like material such as in lettuce.

Another excellent form of dry algae is the dried Nori seaweed. This seaweed/kelp can be found in oriental food stores and comes packaged in sheets as thin as newspaper. There seem to be a few different types, e.g., green, red, and brown varieties. My fishes prefer the green seaweed. I also enhance the dried seaweed with either an all "B" natural vitamin solution (about three drops mixed in a teaspoon of water) with no preservative or a similar vitamin "C" solution. There are also prepared vitamin and mineral supplements that can be used to fortify dry foods, e.g., American Marine's Selcon, which contains highly unsaturated fatty acids (HUFA) and vitamin C, or Kent Marine's Zoe, both excellent products.

Due to the processes involved in producing dried and freeze-dried foods their taste and nutritional value is not as good as fresh, live or frozen foods. They, including krill, should be enhanced with a vitamin/mineral additive. And, where frozen foods are concerned, keep in mind freezing alters their amino acids. So the addition of a vitamin/mineral additive is quite beneficial. Also, care should be exercised as to the amount fed at any one time, especially where flake food is concerned as it begins decaying almost immediately upon contact with water, leaching vitamins or going to waste.

As for lateral line disease/disorder it has always been my position that diet, stress and/or poor water quality (in that order) has been its cause. My personal feeling is that lateral line disorder could be considered comparable to rickets or beriberi in humans. Poor water quality and stress no doubt irritates this condition caused by a vitamin/mineral deficiency and deteriorated areas become a haven for bacteria/infection. Surgeonfishes/angelfishes are mostly herbivores and their diet consists mainly of algae. Micro or macroalgae contain a wide variety of trace metals/vitamins and the lack of proper supply of these may just be the cause of this problem. Broccoli, which contains vitamin C, A, E, and some iodine, is one of the more acceptable people foodstuffs for fishes and can be fed without treating it any fashion except rinsing under tap water before use.

Many years ago the president of a local aquarium society was given a purple tang that had come into a local pet store in the most dreadful condition I've ever seen! It was riddled from head to tail, or what was left of the tail, with what we call "lateral line disease." The fish was placed in a 100 gallon aquarium that contained some Lionfish and lots of good hiding places. The water quality was good and the tang was fed flake food soaked in an all-natural multi-vitamin solution and was also given the excess macroalgae from my aquarium. The flake was fed as often as possible in the beginning, sometimes as many as ten to fifteen times a day. Only a small pinch of treated flake was dropped in the aquarium, never any more than the fish could eat in a minute or two. Within a few months the fish was almost fully recovered and looked like it just came from the ocean! I only wish I had a before-and-after picture. A fellow aquarist from England contacted me during that time and had a similar lateral line problem with one of his angelfish. After trying the above feeding routine he wrote to say his fish was returning to normal.

As for leading edge science, over the past few years words such as immunostimulants, glucans, and probiotics have became buzzwords. Professional aquaculture companies have begun selling treated foods and additives containing compounds that can reduce the chance of infections and/or improve the possibility of recovering from a particular disease.

Enhancing the mechanisms that ward off disease with certain chemicals known as immunostimulants is a growing and worthwhile approach. It is accomplished among other things by increasing the level of macrophages, a particular "killer" white blood cell that devours disease-causing cells and also activates T-cells, which produce antibodies. It also seems to be effective against viral and parasite-related problems. The enhancing, however, is a temporary condition and does not build increased permanent resistance. Any product containing these compounds should be used periodically, as fishes seem to establish enhanced resistance periods for only a short period of time. Manufacturer recommendations should be followed and if unsure always rotate the use of enhanced products, e.g., every few weeks with other quality foodstuffs.

Keep in mind that without an adequate supply of carbohydrates, protein, fats, vitamins and minerals in the diets of our animals, treated foods will be useless. Always feed a varied diet and supplement with known and tested products that truly benefit the animals in the aquarium. And, more of treated foods is not better as their over usage may inhibit the immune system besides wasting money since these products are more expensive than non-treated foodstuffs.

And, the use of good bacteria and/or their byproducts to fight troublesome bacteria has been known for many decades. Encouraging good bacteria to utilize the same growth space that troublesome bacteria would utilize is a way of preventing the initial colonization of disease causing organisms thereby resulting in an overall long-term healthy animal. These desirable organisms are called "probiotics." As for "prebiotics" they are the substances that provoke or inspire the growth and colonization by probiotic organisms.

Enhanced products are especially useful during stressful times when animal immune systems become overtaxed. Shipping, aggression by tankmates, poor water quality and poor diet are a few examples of these stresses. These products are valuable tools in lengthening animal vitality and longevity in our aquariums.

So, in a nutshell, there are benefits to be derived from certain people foods, exactly which ones and in what quantities is still not a perfected science where our pets are involved. And, with the use of treated foodstuffs, the ability to lengthen life spans is becoming a reality. But, even though we are seeing better foodstuff products, it all begins with understanding the needs of your animals.

Hope this helps,

Bob

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