HOW TO DO IT
Pound up your assistant. Take a few deep breaths and relax.
Fill the large bowl with your horse's tank water.
Remove your horse from the tank by gently scooting him into a small container and gently release him into the bowl of tank water.
Have your assistant firmly but gently hold the horse, keeping him submerged at all times. His head and neck should be between their thumb and forefinger, snout pointing up, with his body lying across their palm. Encourage him to curl his tail around their pinky. This will help to keep the horse calm. If you have never held a seahorse in your hand you may be surprised at how strong they are. He may struggle or even snick. Boy oh boy was I surprised at how powerful their snick is.
Take the previously filled and primed syringe into your dominant hand.
Loosely hold the horse's snout between the thumb and forefinger of your other hand.
Closely observe the snout tip. It will open and close in synchrony with his respirations.
As the snout opens insert the tip of the catheter into the snout about ½ way between the snout tip and trigger.
Slowly and gently depress the plunger. Try to time injecting tiny bits of the gruel just prior to the closing of the snout. If he is ingesting the gruel you will actually see him swallow and pass some of the food through his gills. He may snick, it will feel strange but don't be alarmed. The first time my boy did it I thought for sure the catheter would break off in his snout. It never did. He did however dent it a bit. That snick is powerful!
If the gruel is coming back out of his snout either you are injecting the gruel to quickly, the catheter tip is not far enough into his snout or you are close to the end of the feeding and his GI tract is full. First check to see if you are close to the end of the estimated amount of the feeding. If so he is probably full and you are done. If not try injecting the gruel a little slower taking care to try and synchronize advancing the plunger just prior to the closing of the snout. If the gruel continues to come back out try advancing the catheter tip just a tad further. Finish the feeding. You may need to give him and yourself a little break if either of the above situations occur and too much of the feeding is lost. Refill the syringe and give him the rest of the estimated amount.
Wooooooo Hoooooooo!!! That's it! You did it! Tell him what a good boy he was, return him to the tank, give yourself a big pat on the back, thank your assistant and take the rest of the evening off in front of your tank with a cup of tea... well... OK, if you insist a cold beer, a glass of wine, or a good stiff drink of your choice. It wasn't that bad now was it? I bet it was easier than you had anticipated. I thought it was.
Hopefully this information helps.