Re:ok stocking density?

Dear eaglestour:

You’re very welcome to the information, sir! We just try to point you in the right direction so that you can get started off on the right foot.

However, with regard to acclimating your fire shrimp when it arrives, drip acclimation may not be the best option in your case. The painstaking drip-acclimation process works very well for specimens that were obtained locally and bagged up with pure oxygen at their LFS for the short trip home because there isn’t time for significant levels of ammonia or carbon dioxide (CO2) to build up in the bags before acclimation is begun. But drip-acclimating specimens that have been en route for 24 hours or more can be disastrous and may well result in the death of the specimens while they are still in the shipping bag. If your fire shrimp is a ship the long distance, then I would be careful to follow the acclimation instructions that come with it to the letter! Allow me explain.

Acclimating newly arrived livestock properly after their extended cross-country journey is absolutely vital. It’s not like acclimating the new specimens you bring home after a quick trip back from your local fish store. The long distances and prolonged transit times involved make proper care of the new arrivals once they finally reach you a far more urgent matter. The reason for this is that all the while the seahorses are en route, they are excreting wastes and respiring in the dark shipping box — consuming oxygen (O2) and giving off carbon dioxide (CO2). That means two things: deadly ammonia is steadily building up in the shipping bag and the pH is steadily dropping, making the water more acidic.

This downward pH shift is actually helpful in that ammonia is less toxic at low pH and becomes much more toxic at higher pH. This is because ammonia exists in water in an equilibrium between two different forms — a nontoxic ionized form usually referred to as ammonium (NH4+) and an un-ionized form (NH3), which is highly toxic. Ammonium (NH4+) is completely harmless to fishes since the ionized ammonia molecule cannot cross the cell membrane and enter their cells. Note that only difference between harmless NH4+ and deadly NH3 is the addition of a hydrogen ion (H+), which converts toxic ammonia to nontoxic ammonium. At low pH, the extra hydrogen ions (H+) of acidic water are readily available to attach to the ammonia molecule, converting most of the ammonia to ammonium: NH3 + H+ —> NH4+. But at high pH, under alkaline conditions, exactly the opposite occurs. At high pH, the abundance of hydroxide ions (OH-) in alkaline water strips the extra hydrogen ion (H+) away from ammonium, rapidly converting most of it to deadly ammonia: OH- + NH4+ —> NH3 + H20. In other words, the higher (more alkaline) the pH, the more ammonia is present in the dangerous un-ionized form (NH3), which easily crosses cell membranes and enters the body.

This should make it easier to understand exactly what is happening in the shipping bag. As the seahorses breathe, consuming O2 and giving of CO2, the pH of the water drops and more of the ammonia (NH3) they produce is assimilated into harmless ammonium (NH4+). So the decrease in pH that occurs during long-distance shipping is actually protecting the new arrivals somewhat — until we open the shipping bag! Once the shipping bag is opened, CO2 begins offgassing from the bag water and fresh O2 begins entering the water, and as the pH begins to rise in response and return to normal, the ammonia in the water becomes increasingly poisonous. And when we begin to add alkaline water with a pH of 8.0-8.4 from the main tank to the shipping bag, we are accelerating the pH shift and converting ever more of the ammonium (NH4+) to deadly ammonia (NH3). The suddenly high concentration of ammonia in the water quickly diffuses into the seahorse’s cells, and acclimating the new arrivals becomes a race against ammonia poisoning just that quickly.

Acclimating farm-raised seahorses (or decorative fire shrimp, in your case) properly is therefore the art of achieving the proper balance between two conflicting needs: the need to get them out of the toxic shipping water as quickly as possible and the need to allow them to adjust to tank conditions as gradually as is practical. So if your fire shrimp is coming to you from afar, drip acclimating it may simply take too long for its own good. Under the circumstances, it’s better to follow the acclimation instructions that come with your shrimp precisely.

Otherwise, drip application is definitely the way to go when you bring home decorative shrimp from your LFS. But it doesn’t sound like that is the case with your fire shrimp, so proceed accordingly.

Best of luck with your fire shrimp tomorrow, eaglestour! They are magnificent specimens and great tankmates for seahorses once they’ve grown a bit.

Happy Trails!
Pete Giwojna