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egardless of the food type that is used, it is of PARAMOUNT importance that Xiphophorus fish are properly fed. There is NO exact formula for feeding these fishes since they can greatly vary genetically. If they are underfed, they do not develop properly or can die. Fry can become stunted if not fed adequately and given adequate space. An overfeeding condition, on the other hand, usually results in an increase of nitrates in an aquarium. Such a condition can result in the death of a fish as well. A good protocol to follow when feeding flake food is the "ten-minute rule". A person feeds and moves on to other tanks, only to come back ~10 minutes later. If the fish have finished the flake food at the surface of the tank, the person should feed a small amount more. If they have not finished the food and are showing little or no interest in the food, the caretaker should use a net to remove excess food. This technique is especially important for stock tanks with a large number of fish, since it is particularly difficult to gauge the proper amount of food. Recipes follow.

Harvesting Artemia salina (Brine Shrimp)
Easy Protocol
For one 5 gal carboy:

Prepare 5 gallons of salt water solution by using Instant Ocean (8141 Tyler Blvd, Mentor, OH 44060; 1-800-822-1100) and following the manufacturer's directions. The salinity or specific gravity of the water should be between 1.01 and 1.02. This can be checked using a commercially obtained hydrometer. Add 4 tbs of brine shrimp eggs (OSI Pro 80, OSI Marine Labs, 3550 Arden Road, Haywood, CA 94545; 1-800-423-3447). The carboys need a robust degree of aeration for 48 hours. At that point the air lines are removed and the brine hatchlings are allowed to settle on the bottom, away from the unhatched eggs which float to the top. We use a powerful light source next to the carboy, as hatchlings cluster towards the light source. This separation process usually takes 30 minutes. A valve at the bottom of the carboy is opened and the effluent is passed through a fine net ("brine shrimp net"). The valve is stopped just before the unhatched egg layer reaches the bottom. The live brine shrimp are moved into Lee specimen containers containing Startright treated water. Using a plastic bulb-type pipetter, siphon and release the brine shrimp into the water. Try not to overfeed, since fish have trouble stopping when live food is about.

Alternative protocol
Decapsulation of Artemia salina (Brine Shrimp) cysts
For one 5 gal carboy

In a 2000ml beaker add 810ml chilled fresh water and 3 tbsp. brine shrimp cysts. Gently aerate for 1 hour. This re-hydrates the cysts. After 1 hour, add 400ml ultra bleach (540ml regular bleach) to beaker. Continue aeration and stir solution continuously for 5-10 minutes. Decapsulation is complete when almost all of the cysts are orange. At this point pour the solution through a brine shrimp net to catch the eggs and rinse immediately with DI water (or cold tap water). Rinse cysts for at least 5 minute - until the bleach smell is gone. In a 400ml beaker add 2 tbsp. Startright and 350-400ml DI water. Stir this and set net with the cysts in the solution for 5 minutes while stirring the cysts in the net. Make sure all of the cysts are submersed in the Startright. This neutralizes the residual chlorine bleach. Finish by pouring the solution through the net and rinse the cysts again with DI water for 2 minutes. Now the cysts are ready to go into the brine water for hatching.

For multiple 5 gal carboys

When re-hydrating the cysts use 1000ml chilled water. To this add 6-9 tbsp cysts (possibly 12 for 4 carboys). Aerate for 1 hour and make sure the eggs don't sit on the bottom of the beaker. When decapsulating the cysts with the bleach use 700ml ultra bleach. It may take the cysts a little longer to turn the orange color (5-10min.). Rinse immediately once they turn orange for 5-10 minutes. Cysts may need to be split between two nets. Neutralize residual bleach with Startright, and rinse again like for one carboy. Make sure bleach smell is gone. Split cysts to go into however many caryboys are being prepared and hatch.

Liver Paste

Recipe is for 5lbs. preparation
(modified from Dr. Myron Gordon's formula, 1943)

Ingredients

• 5lbs. of fresh beef liver (rinsed)
• 4 8oz. boxes of "Gerber Oatmeal Baby Cereal"
• 5 large freshly graded carrots
• 1 lb. fresh spinach
• 83 mg. Potassium Iodine/ 5 lbs. of liver
• 5 8 oz. cups of water

Apparatus and miscellaneous

• food processor
• zip lock bags (gallon size)
• strainer
• 4-gallon bucket
• stirring paddle/electric drill
• paddle spoons
• rolling pin

Preparation of Liver Paste

1. Grate one large carrot and a few leaves of spinach in the food processor.
2. Add one lb. of beef liver, and one cup of water to the processor: Puree contents.
3. Pour the liquidized liver through the strainer into a four-gallon bucket.
4. Repeat until all liver is liquidized and strained. Discard waste liver that did not pass through the strainer.
5. To strained liquidized liver, add a premixed combination of:
• 2-1/2 tbs. table salt
• 83 mg. potassium iodine
6. Add baby cereal, stirring thoroughly all the time. Add enough cereal to result in a thick, peanut-butter-like consistency. (Use of a drill with a stirring paddle will expediate this process.)
7. Transfer mixture to microwaveable cooking tray. Fill each tray about half full.
• Microwave for five min.
• Stir, esp. to avoid overcooking the edges
• Microwave two more times at five min. intervals-stir after each (avoid overcooking)
8. After cooking is completed, place liver paste in zip lock bags, and roll out paste with a rolling pin until a flat sheet of about .25 in. is obtained. Repeat until all the liver paste is in zip lock bags.
9. Place 'sheets' of liver paste in the freezer for two days before use.

Feeding should be done by pinching off small portions of the liver paste and dropping them into the tanks. The fish may not feed on such food immediately if they are not accustomed to the food type. Excess liver paste on the bottom of the tank should be removed if not consumed within ~2 hours.

Contributed by Leona Hazlewood, Steven Kazianis, and Ron Walter.

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