So many of us aquarium keepers focus on our successes and try to forget about our failings. I think it's important to document both.
Keeping seahorses and pipefish is not easy. What makes it more difficult is when you don't follow the rules.
Rule#1. QUARANTINE for at least a month. Especially if you have wild caught Syngnathids, you'll want to deworm.
Rule#2. Don't let the temperature rise above 74 degrees Fahrenheit. Syngnathids are prone to an infection from Vibrio bacteria. I'm not a pathologist, but it was explained to me by a pathologist--when the temperature rises above 74 degrees, a protein in the Vibrio bacteria changes, and the seahorses' immune system won't recognize it. Also, when the temperature is this warm, the Vibrio becomes both more aggressive and infectious and reproduces faster. If your Syngnathid ever becomes infected, move it to a hospital tank and lower the temperature to 68 degrees. Then go on Seahorse.org and ask for help!
Rule#3 Don't mix seahorses from different locations, different species of seahorses, or different species of Syngnathids (including pipefish). The reason, again, is Vibrio. Different species of seahorses and pipefish and even those from different locations (e.g. breeders) carry different strains of Vibrio. With little exception, all Syngnathids are asymptomatic carriers of Vibrio, meaning, they carry the disease without symptoms or infection. So mixing a seahorse with a pipefish means that different strains of Vibrio (and various other pathogens that may be linked to that species) are going to be introduced. This would be similar to the plagues given to the Native Americans when the Europeans came to their continent. This can have disastrous results!
Dilution and cleanliness may be another piece to the mixing Syngnathids puzzle. In our aquariums, fish are stocked much more heavily than they would be in the wild (compared to water volume). Bacteria can reproduce quickly and reach plague proportions. Doing large, regular water changes and siphoning all decaying matter from the aquarium can go a long way toward healthier seahorses. Bare-bottomed aquariums are very easy to keep clean; scrub the walls and bottom of the aquarium regularly in addition to siphoning detritus and large water changes.
I have a 55 gallon main tank with a 37 gallon tank plumbed inline. The tanks have a chiller that keeps the temperature between 68 and 73 degrees, depending on the season. Right now, I'm keeping it around 71 to get ready for spring and warmer weather when I'll let it run warmer to help keep my chiller from wearing out.
There are bluestriped pipefish and Erectus seahorses in there right now. I've had other species of pipefish in these tanks at various times, but none have survived to date
Basically, I've had just about every kind of Syngnathid possible in this tank. I come across a lot of them in my line of work, and it's hard not to bring everything home. Most didn't survive, but I don't think it's mainly due to mixing species. It's definitely possible that it was a factor, but the main cause of death for the pipefish I've had has been starvation or probably weakness caused by emaciation.
July 07: I got two bluestriped pipefish. They were quarantined for over a month and taught to eat frozen food. They are still alive today and are fat and healthy. their seahorse.org thread
Jan 09: added a D. pessuliferus and D. dactyliophorus. One week quarantine, taught to eat frozen. Died five days later, uncertain of cause. Now that I've seen more of these animals, I realize how thin mine were when I got them.
Around the same time, dragonfaced pipefish were put in quarantine (right after the bandeds came out). They were in pretty bad shape up upon arrival, ragged tail and pretty skinny. I never once saw either of them eat anything, not even live copepods. Kept alive for two months, then one got snout rot and died, the other got thinner and thinner till it died.
Sept 08: I suddenly acquired a Redstripe pipefish and a ghost pipefish. Ghost pipefish are nearly impossible to keep in aquariums, even public aquariums. I would never get one on purpose, but this one was a gift. Unfortunately, both were extremely thin. I went on vacation that week to get married and had "the fish guy" from work come over to take care of them. Neither survived.
Sept 08: got my first seahorses, a pair of large adult true CB Erectus originally from Carlsbad Aquafarms. They came in really healthy and ate well. Still doing really well. They were quarantined for several weeks.
Recently, the really skinny stick pipefish (pictures in a previous post) never ate and died a couple days later.
Feb 09: got three new true CB juvenile erectus seahorses originally from Mexico. Quarantined and de-fluked in the same system and manner as the first seahorses. They are eating well and very active.
The day before yesterday, one of my juvie erectus seemed to be having trouble eating. Yesterday when I came home from work, I noticed that he was "playing" with his trigger a lot. It's wasn't exactly stuck, but it seemed "sticky." I gave him a 10 minute FW dip, and he didn't thrash a lot or get very stressed out. Minutes later, he was back to normal and chasing down his food. He ate a lot last night and today. I will keep an eye on him. I have immediate access to any medicine. April update: never showed symptoms again, full recovery.