Okay, if your new 20-gallon aquarium has been running with just the water in it and everything is working properly with no leaks, you can go ahead and add the artificial salt mix, sand, or live rock, or any nonliving decorations you would like to include at this time. You will then need to cycle the aquarium to establish a large population of the beneficial nitrifying bacteria that carry out biological filtration. The aquarium cannot support any life until it has cycled. It typically takes 4-6 weeks for an aquarium to cycle from scratch and once the cycling process is complete, you’ll want to wait a while longer for the aquarium to stabilize and for the biological filtration to become well-established before you begin stocking the tank. It will therefore be at least eight weeks from the time you begin cycling the new aquarium until you can begin adding the living specimens.
Once the aquarium has completed the cycling process, it is customary to begin stocking the aquarium by adding the cleanup crew (assorted snails and perhaps a few seahorse-safe microhermit crabs) and the decorative living macroalgae first, birdle. Many hobbyists like to wait 4-6 weeks after they add the sanitation engineers or cleanup crew before they introduce any more fish or invertebrates. This waiting period serves as a de facto quarantine protocol for the aquarium janitors and allows the new aquarium more time to stabilize and mature.
Only after this point, when the cleanup crew has been in the tank for an additional 4-6 weeks with no problems, should you consider carefully introducing seahorse-safe live corals or peppermint shrimp. Remember, patience is a great virtue when stocking a new aquarium. You never want to add too many new specimens to quickly. You want to give the biological filtration a chance to adjust to the heavier bioload after introducing any new specimens before you continue stocking the aquarium. Introducing too many specimens to a new tank at the same time can result in ammonia and/or nitrite spikes that can be very harmful to fish and invertebrates.
When you are ready to begin adding the fish, it’s best to add the most docile, peaceful fish first and let them become established in the aquarium before you add the other fish on your wish list. If possible, I like to introduce the seahorses before any of the other fish so that the ponies are the established residents in the aquarium when the other fish are added.
And remember to quarantine any new fish purchased from your local fish store or other retail outlets to make sure they are healthy and disease free before you introduce them into your main tank.
Yes, that’s correct — a chocolate chip starfish could be a risk to your seahorses and can injure or kill them. But that does not mean that you cannot keep starfish in your seahorse tank. There are more colorful starfish such as any of the Fromia seastars that do great with seahorses. I suggest you pick out two or three of the brightly colored little Fromia starfish instead of a chocolate chip starfish.
Yes, I am saying that you cannot keep a Mandarin goby or a scooter blenny in a 20-gallon aquarium, even if it is only one of each. They are pod eaters that subsist primarily on live copepods and amphipods within the aquarium, which means they do best in large (100+ gallons), well-established reef systems loaded with live rock and live sand. A Mandarin goby or scooter blenny would slowly starve to death in your 20-gallon aquarium.
But the most important thing you can do at this point, birdle, in order to assure that everything goes smoothly while you are establishing the aquarium and preparing it for your seahorses, would be to contact me and begin the Ocean Rider seahorse training program. The very first lesson explains how to optimize your aquarium to create ideal conditions for the seahorses in great detail, and the second lesson includes step-by-step instructions for cycling a new marine aquarium from scratch so that you know exactly how to proceed. Subsequent lessons discuss everything else you need to know about the care and keeping of seahorses, including compatible tank mates, breeding and raising them, and disease prevention and control.
Please send a brief e-mail with your full name (first and last) to the following address, and I will get you started out with the first lesson of the seahorse training course and work with you personally from then on until your new aquarium is up and running, with the biological filtration fully established, ready for the seahorses in your other fish:
Best of luck with the final preparations for your new 20-gallon aquarium, birdle!