Taking care of shrimp throughout their life cycle can be challenging, especially if you are new to aquarium keeping.
When shrimp undergo the molting process, they are especially fragile, and many lethal problems are known to develop at this stage in your shrimp’s life.
Read on to learn about the normal molting behaviors of shrimp, problems that can occur during the molting process, the causes of these problems, and what to do about it when your shrimp has trouble molting.
Common molting behavior
Lethargic behavior
During molting, most shrimp exhibit lethargic behavior and will appear to be much more lazy than usual.
Shrimp may sit mostly still for a few days, while only fanning their scales or moving their antennas around slightly.
If they do walk or swim around the tank, they are not likely to travel a large distance or exert much effort.
Many new shrimp keepers notice that their shrimp have remained in the same place for a few days and tend to assume that there is an issue with their health.
In reality, this behavior can be normal during the molting process and is not always a cause for concern.
Refuse food
Due to their lethargic behavior, many shrimps refuse their food because they are simply too tired to eat.
In addition, certain aspects of eating and digestion can complicate the molting process, such as if food or waste particles become lodged between the new and old layers of your shrimp’s exoskeleton.
Even if your shrimp refuse food for a few days, this is considered normal behavior during molting, and it is important to know that they are not at risk of starvation.
Hiding
After molting, shrimp become extra sensitive as their new exoskeleton takes a while to harden. Because of this, freshly molted shrimp will likely hide from others, and may also avoid bright areas of the tank.
During this period, shrimp should gradually begin seeking out food again. They may still be somewhat slow-moving and gentle in their behaviors until their new shell is fully ready, but at this stage, your shrimp are mostly safe.
At this point, following the molting process, the mating cycle begins.
Problems with the molting process
Problem 1: White ring
White ring is a visually descriptive name for a deadly molting condition that occurs when a crack appears between your shrimp’s carapace and thorax.
Normally, the old exoskeleton is supposed to break apart in certain places only, allowing for it to hinge open and provide an easy escape for the shrimp.
However, the white ring indicates that the old shell has broken in several places, typically all the way around your shrimp.
Now that the old exoskeleton is divided into two separate pieces, it is especially difficult for your shrimp to remove.
This condition tends to be deadly because it removes the shrimp’s ability to use leverage to escape the old shell, often earning the name ‘white ring of death’.
Problem 2: Stuck in molt
Shrimp that are stuck in molt have become trapped in their old shell, typically for other reasons than the unique problem described with the white ring of death.
The shell may be broken in other incorrect places or too tough to break apart at all, trapping the shrimp inside. This condition tends to paralyze the shrimp, making them lay on the ground.
Although some shrimp owners have reported instances where shrimp have been able to free themselves over time, shrimp that become stuck in molt typically die from this condition.
Causes of molting problems
Poor water conditions
The most common cause of molting problems in shrimp is poor water conditions. There are many important water chemistry factors that must be balanced in order to facilitate the molting process.
These factors include the general hardness (GH), carbonate hardness (KH), overall acidic balance (pH), and total dissolved solids (TDS) present in your tank water.
To determine the exact condition that is in a state of imbalance, you will need to test your tank water for these properties.
Testing and maintaining these chemical properties of your water is vital for maintaining shrimp health throughout their life cycle, especially during the molting process.
Insufficient nutrients
The second most common cause of shrimp molting problems is inadequate diet, or a lack of sufficient nutrients in your shrimp’s food.
Shrimp need an adequate food source that is intended specifically for them, and cannot rely on leftover fish food, aquarium plants, or kitchen scraps alone if you want your pets to remain healthy.
Shrimp require a diet that has balanced amounts of protein and calcium. These nutrients help the shrimp develop and form a strong, new exoskeleton during the molting process.
Insufficient nutrients are associated with brittle shells and related problems, such as the white ring of death.
Should I help a shrimp that’s stuck in molt?
Most of the time, if your shrimp has developed the white ring of death or is otherwise stuck in the molting process, it will be fatal.
Although there have been reports of some shrimp being able to free themselves eventually, this is the best-case scenario.
Getting stuck in molt is a very common cause of death among pet shrimp, as many tank owners struggle with getting adequate nutrition and water balance on the first try.
In extreme circumstances, some shrimp owners have used tweezers to attempt to remove the stuck portion of the old exoskeleton from their shrimp and have been successful.
However, we highly encourage that you avoid attempting this method at all costs.
Shrimp are frail and can be easily damaged by tools such as tweezers, so this type of work carries a high risk and must be done with the utmost precision.
Even in the hands of someone skilled, much luck is involved in ensuring that the shrimp comes out unharmed after this process.
Intervening with a shrimp that is stuck in molt may feel like the right thing to do. Still, because of the high likelihood of further injuring, traumatizing, or scaring your shrimp while they are already dying, we encourage you to hope for the best and let nature take its course in these situations.
What to do about molting problems? (3 tips)
Tip 3: Improve shrimp diet
As we mentioned earlier, shrimp need a diet that has adequate amounts of both protein and calcium.
These factors should also be well-balanced with other nutrients from both plant and animal sources, and can often be provided in the form of shrimp-specific, sinking tablets.
Sinking food is mandatory for aquarium shrimp due to their poor swimming ability.
Food that floats along the surface of the water will be almost impossible for them to reach, and they may stress themselves out by trying to swim towards it.
Selecting a sinking variety of pellet intended for shrimp is essential because it is easier for your shrimp to find, and it also produces less water pollution.
Algae tablets also make a great addition to your shrimps’ diet, especially if they are not already feeding on tank plant waste or kitchen vegetable scraps.
Algae tablets are incredibly high in nutrients, including minerals like calcium; you can almost think of them like shrimp vitamins!
Because algae tablets are not known to have a high protein content, this option is only viable in addition to another, more balanced food.
Tip 2: Improve water conditions
First, use a test kit to measure the general hardness (GH), carbonate hardness (KH), overall acidic balance (pH), and total dissolved solids (TDS) in your tank water.
Ideal GH levels for shrimp fall between 4-8dGH, while the ideal KH levels for them fall between 3-15dKH.
Freshwater shrimp prefer a pH level between 6.8-7.5, and a TDS reading in the range of 200-300 parts per million (ppm).
It’s important to remember that these ranges are a general guide for freshwater shrimp.
Many species have more specific water perimeters that must be followed to ensure the health of your shrimp, so always do your research diligently.
If any of your levels fall out of the appropriate ranges, you will need to take steps to adjust them.
Tank additives that alter water chemistry are available at fish supply stores, and chemical options or more natural products are available to suit your needs.
If your tank’s source water is naturally high in TDS, you may need to mix it partially with distilled water before adding it to your tank in order to balance out the number of dissolved solids.
Tip 3: Avoid large or quick water changes
Some molting problems are caused by routine water changes that either involve too large of a volume of water being exchanged or fresh water being added to the aquarium too quickly.
Shrimp get stressed very easily by changes in water perimeters, such as the qualities we discussed above.
Avoiding drastic changes in these qualities is essential when working to facilitate a healthy molting process.
Shrimp in the process of molting is especially prone to harm during large or fast water changes. In these cases, their failure to adapt to the changing water conditions leads to rapid death.