I’m very sorry to hear about the disease outbreak that caused the loss of your seahorses!
If you believe the infectious disease was due to Vibrio or Pseudomonas bacteria, which are highly infectious and very difficult to eradicate from an aquarium, then it would be appropriate to break down the tank, sterilize everything, and start over from scratch. Since you have had an outbreak of a highly contagious infection that was transmitted from one seahorse to the next and eventually killed all of the ponies, Laura, I think it would be prudent to sterilize the tank and all of the equipment in it, and then recycle the aquarium from scratch again before you consider keeping any new fish in the aquarium. And I would be very careful not to spread the infection from the contaminated tank to any of your other aquariums.
Do NOT disperse your live rock, substratum, macroalgae, equipment or accessories from the infected tank to your other aquaria, Laura, or you risk inoculating them with Vibrio/Pseudomonas and spreading the infection to all your tanks! And you must be extremely careful to avoid accidentally cross-contaminating your other tanks from your infected seahorse tank. Any nets, hydrometers, or other equipment used in your seahorse tank should be sterilized after every use and not placed into or used in any other tanks. Avoid working in your seahorse tank or your hospital tank with your bare hands, scrub/disinfect your hands and arms thoroughly after working on your seahorse tank, and do not place your hands in the seahorse tank and then place your hands in another aquarium. These bacteria can even be transferred from one aquarium to another by splashing water droplets or as an aerosol via the mist generated from a protein skimmer or an airstone. Be careful!
Sterilize the seahorse tank and all the equipment it contains by using a strong bleach solution and then air drying it completely. To be on the safe side I would discard the live sand or gravel substrate and any macroalgae in the aquarium, but you can attempt to recycle the live rock by sterilizing it, converting it to dead rock, reseeding it with beneficial bacteria, and then allowing it to be slowly recolonized by healthy sessile life. Once the rock has been sufficiently sterilized, it can be placed in a sump or back in the main tank to regain its bacteria bed and time will do the rest.
Here is the method that Paul Anderson (Department of Fisheries and Aquatic Sciences, University of Florida) recommends for sterilizing systems with stubborn Mycobacteria infections (mycobacteriosis is another very stubborn infection that is contagious and difficult to eradicate):
"Effective disinfectants against mycobacterium include spraying with 70% Ethanol and allowing the equipment to air-dry, and bleach baths (I use 50ppm bleach baths with a minimum contact time of one hour, this has been reported to be effective against M. marinum) followed by sodium thiosulfate neutralization baths. Ultraviolet light sterilization is also recommended in myco-positive systems. If you’ve got myco-positive tanks among other systems, common sense suggests performing husbandry on these systems last in your rounds.
"A note on ethanol: I have found in my experience that seahorses are very sensitive to ethanol, so I advise being very cautious to avoid overspray into adjacent tanks (Paul Anderson, pers. com.)."
So if you want to be really sure you are eradicating any disease organisms in your seahorse tank, Barbara, you might first disinfect the affected tank and all of its equipment with 70% ethanol, allow it to air dry, and then set it up anew and fill it with freshwater, start everything operating again, and administer a good stiff dose of chlorine bleach for as long as it takes for you to feel confident of the results. That will assure that the bleach solution is circulated throughout your protein skimmer, filters, and all the other equipment, thus sterilizing them early both inside and out. I can’t imagine any marine pathogens or parasites that could survive the ethanol disinfection process, followed by prolonged immersion in freshwater treated with an effective dose of beach.
The appropriate dosage is 1 cup of chlorine bleach for every 50 gallons of water in the aquarium. Keep the filters running on the hospital tank while you treat it with the chlorine bleach so that they are thoroughly exposed to the chlorine as well. Give the chlorine about two days to sterilize everything in the aquarium — nets, accessories and all. After 48 hours, you can add chlorine neutralizer to your hospital tank to remove the bleach, change out all the water, and rinse everything very thoroughly with freshwater. Keep your fish room well-ventilated while you’re treating the hospital tank with the chlorine bleach and be careful not to breathe in the chlorine fumes when you’re handling the bleach.
Once you had run the aquarium with freshwater and bleach for long enough to be quite sure that any disease organisms had been eradicated, you could use sodium thiosulfate to pull out the bleach, and add artificial salt mix to achieve the desired salinity/specific gravity. With this method of sterilization, you can keep your skimmer, ultraviolet sterilizer, pumps and powerheads, etc., since all of the equipment gets sterilized thoroughly along with the rest of the tank.
One note of caution: whenever you are using significant amounts of chlorine bleach, it’s very important to work in a well ventilated area and avoid inhaling the fumes. Also be sure to take whatever precautions are necessary to prevent those fumes from entering any nearby aquaria with live specimens via air pumps.
And, as Dr. Anderson noted, when you’ve had a disease outbreak that warrants breaking down and sterilizing the system, it’s a good idea to install and maintain UV sterilization on that tank in the future when it’s up and running again.
The best way to sterilize the live rock is often to remove it from the aquarium, place it in a large container of water, and boil it thoroughly. The boiling water will effectively sterilize and purify the live rock, which is then safe to use again after it has been air dried. (Sometimes aquarists will sterilize the live rock by soaking it in a strong solution of bleach or vinegar, but sometimes the bleach or vinegar will soak deep into the porous interior of the live rock and be leached out of it gradually for a long time thereafter, so it can be difficult to remove all traces of the bleach or vinegar before its placed back into the aquarium. For this reason, boiling the live rock is often a safer way to sterilize.
Once the aquarium and all of the associated equipment and accessories have been sterilized, and the aquarium has been refill with saltwater adjusted to the proper pH and salinity, you can place new live sand in the aquarium, which will reseed the tank with beneficial nitrifying bacteria, and then place the sterilized live rock back in the aquarium and cycle the entire tank anew. The cycling process is exactly the same as when you set up a brand-new aquarium, and the beneficial Nitrobacter and Nitrosomonas bacteria will recolonized the live rock during the cycling process.
If you don’t like to use live sand in your seahorse tank for any reason, Laura, then you can simply add a little BioSpira to seed the aquarium and live rock with beneficial bacteria instead. Bio-Spira is a product offered by Marineland which contains the live bacteria necessary to convert ammonia and nitrite into harmless nitrate. It is available for both freshwater and marine aquariums, so of course be sure to get the Bio-Spira for saltwater. Just use it as explained below and it will help your aquarium to recycle more quickly:
BIO-Spira is a "live" bacteria culture that is sold refrigerated and must be kept refrigerated until used. It can not be overdosed. Repeated dosing of your aquarium with ammonia removing liquids (such as BIO-Safe, Amquel, Ammo-lock and Aqua-Safe) can inhibit the beneficial action of BIO-Spira. Ammonia removing liquids should only be used to initially treat tap water. It is normal to have a small (<2 ppm) amount of ammonia or nitrate during the first few days after set-up. These concentrations are not harmful and will quickly drop to zero with proper use of BIO-Spira.
DIRECTIONS FOR USE:
Shake well before each use. Use 1 ounce (29.6 ml) of BIO-Spira per 30 gallons of water. BIO-Spira cannot be overdosed. Keep refrigerated. Be sure to shut off any UV sterilizers and remove medication by means of a water change or activated carbon.
There is a slight chance that the cleanup crew could also be harboring some of the harmful bacteria and act as a disease reservoir, Laura, but it’s fairly unlikely. For one thing, invertebrates in general are not susceptible to the same pathogens and parasites that plague seahorses and other marine fishes (i.e., vertebrates). If they were carrying any of the parasites that could bother seahorses, it would be as hitchhikers, and that’s unlikely because those same parasites normally cannot survive long without a suitable fish host.
Secondly, snails and invertebrates in general cannot tolerate the usual prophylactic measures we apply to marine fishes when we quarentine them or treat them prophylactically. For example, neither shrimp nor many types of snails can withstand hyposalinity let alone a freshwater dip. Nor do they tolerate the usual chemi-therapeutic agents we normally use to cleanse quarantined fish of parasites, such as formalin, malachite green, copper sulfate, dylox, Panacur, praziquantel, Parinox, metronidazole, etc.. So there is nothing that you could treat your aquarium janitors with to eradicate any pathogens or parasites they could be carrying that would not also kill your sanitation engineers in the process.
In short, Laura, you basically have three choices regarding the decorative shrimp, snails, and micro hermits from the cleanup crew in the infected aquarium. First of all, you can destroy them and be 100% certain they will not reintroduce any disease organisms to the aquarium after it has been sterilized. That is the safest and surest method of dealing with the invertebrates from the contaminated tank, and is not too great of a sacrifice when it is only snails or microhermit crabs that are being euthanized and discard, since they can be replaced fairly inexpensively. But with an expensive fire shrimp, as well as some peppermint shrimp, I can certainly understand that that may not be an especially attractive option for you.
Secondly, if you have a dedicated invertebrate tank that houses no fish, you could consider relocating the cleanup crew from the infected aquarium to the invertebrate tank. Any bacteria or pathogens they are carrying should not cause any problems in the tank that just contains other invertebrates, since they are only pathogenic when they have a vertebrate host to infect. That’s a possibility but one I would not pursue, since you risk spreading the infectious organisms to another tank…
Thirdly, you could quarantine the cleanup crew from the infected aquarium for a period of six weeks while your seahorse tank was being sterilized and recycled. Any parasites the invertebrates from the cleanup crew could possibly have been carrying that could pose a risk to the seahorses would require a vertebrate host in order to survive, and after six weeks without any fish in the aquarium, any such parasites should have been eliminated and are no longer a cause for concern. (Obligate parasites cannot survive an extended period of time without a suitable vertebrate host.) So after the the invertebrates have been isolated for six weeks, they could be returned to the sterilized and recycled main tank with little risk of introducing anything harmful. You could not be 100% certain with this method, but the risk would be slight.
So I would suggest breaking down your seahorse tank, discarding the substrate, boiling the live rock so it can be reused, and then sterilizing the aquarium and cycling at all over again from scratch, Laura. While you are doing so, I would like you to enroll in Ocean Rider’s new training course for seahorse keepers, which includes one entire lesson devoted solely to disease prevention and control. This basic training is very informal and completely free of charge. Ocean Rider provides the free training as a service to their customers and any other hobbyists who are interested in learning more about the care and keeping of seahorses. It’s a crash course on seahorse keeping consisting of 10 separate lessons covering the following subjects, and is conducted entirely via e-mail. There is no homework or examinations or anything of that nature — just a lot of good, solid information on seahorses for you to read through and absorb as best you can, at your own speed:
Aquarium care and requirements of seahorses;
Selecting a suitable aquarium for seahorses;
size (tank height and water volume)
aquarium test kits
Optimizing your aquarium for seahorses;
water movement and circulation
hitching posts (real and artificial)
Cycling a new marine aquarium;
The cleanup crew (aquarium janitors & sanitation engineers);
water quality & water changes
aquarium maintenance schedule
Compatible tank mates for seahorses;
Courtship and breeding;
Rearing the young;
Disease prevention and control;
Acclimating Ocean Rider seahorses.
That way, you could be learning more about seahorse husbandry while your aquarium is being rejuvenated and reestablishing the nitrogen cycle and biological filtration. By the time the tank is ready for more seahorses, you will have completed the training program and can feel confident that your next seahorses will thrive and prosper under your care. If you would like to try the seahorse keeping lessons, just send me a quick e-mail off list ([email protected]) with your full name (first and last), and I will get you started on the training program right away.
Best of luck restoring your seahorse tank so that it’s better than ever before, Laura!