Will a Tarantula Drown in a Water Dish?
The topic of water dishes has the tendency to become highly polarized within the tarantula keeping community. There are some keepers who adamantly oppose using them and others who always offer their tarantulas water dishes. If you’re new to the hobby and researching whether or not a tarantula needs a water dish, then it wouldn’t be a surprise if you’re still confused after doing a quick search!
Tarantulas do not require a water dish, they will survive just fine with water being dropped on their web, the occasional flooding of an enclosure corner, and the moisture that they get from their food. This is where the controversy largely stems from. However, most tarantulas will readily drink out of a water dish if it’s offered to them, and keeping a source of constant water available can prevent accidental deaths due to dehydration which is a common beginner mistake.
Tarantulas are highly unlikely to drown in a dish, even as babies, so there isn’t any compelling reason not to offer them one as long as it fits in the enclosure. A water dish does not pose a risk to a healthy spider. It’s a common misconception that tarantulas will drown in their water bowls without a sponge.
How do tarantulas get water?
A tarantula gets moisture from its prey items, water that accumulates on the substrate, drops that get on its web, and its water dish if you offer one. They draw water up into their mouths, located behind the chelicerae, through something called a pumping-stomach.
If you’ve ever looked at the underside of your tarantula before you may have noticed how their fangs are bordered by a triangular-shaped fringe. This is where the mouth is.
They don’t breathe out of their mouth as we do, which is one of the reasons why they don’t drown in their water dishes. Instead, they have book lungs, which are located on the bottom side of the abdomen. Tarantulas have four of these book lungs.
Can tarantulas drown in a water dish?
A tarantula will not drown in its water bowl. In fact, tarantulas have a hydrophobic cuticle and will float on top of the water surface because they don’t break the surface tension.
Think of what happens when you are trying to determine the sex using a molt. If the exuvia isn’t rehydrated with water that has dish soap in it to bypass the hydrophobic barrier, then the water will slide right off leaving the molt completely dry.
As long as the water isn’t submerging the book lungs the spider is in no danger. To drown, a tarantula would have to be already unhealthy or otherwise unable to escape from the water while their book lungs are submerged for an extended period of time. They use very little oxygen, so it would take quite a long time for this to happen.
Two scenarios coming to the top of my head at the moment where an adult tarantula would drown are if the spider got caught in a body of water with a strong current and it repeatedly got pulled under, or if its burrow got flooded for an extended period of time (like a tarantula getting trapped inside a burrow during monsoon level flooding).

Can tarantulas actually swim?
As a general rule, tarantulas only swim out of necessity and do not go out their way to seek out bodies of water. That being said, a tarantula can stay afloat on the surface if it finds itself on an expanse of water. An example of this happening would be a tarantula falling onto a pool of water after being chased by a predator, or a tarantula encountering a flood during heavy rain.
It isn’t swimming in the sense that they are diving underneath the water. Rather, the tarantula rows on the surface of the water, using its first three pairs of legs to do the actual swimming and allows the back legs to drag behind it.
H. gigas is an exception to the rule above. It’s a fascinating species that displays hunting behavior around water, and can even dive underneath the water to catch prey.
Tarantulas will even willingly submerge themselves in their water dishes sometimes. It isn’t uncommon to see forum posts where keepers are talking about spiders that have made a mad dash for the water dish when they got spooked and then proceeded to sit in it until the perceived threat is gone.
Is it safe to give baby tarantulas water dishes?
There are two main opinions on the safety of giving water dishes to slings, and it’s definitely a loaded topic when it gets asked on the forums. In the end, you will have to make a decision based on the research that you do and your personal comfort level.
Some people feel that it isn’t worth the risk to the spider when they’re so young and fragile because they are able to get all the moisture they need from their food and the dampened substrate. They feel that tiny tarantulas are a high risk for accidents, whereas adults and juveniles are not. Occasionally, people only offer tiny dishes to terrestrial slings and stick to misting the web for arboreals.
Other people are very adamant that out of all the life stages the slings are the ones that need supplemental water offered the most because they can dehydrate so easily and that it would be foolish not to do so. A sling desiccates quickly because it lacks the waxy cuticle that prevents older spiders from drying out easily.
That being said, many experienced keepers don’t offer slings water dishes for reasons other than drowning. For example, the vial they are being kept in may not have enough space for a dish. Some feel that water dishes are redundant and that they don’t need one since a sling is already on moist substrate and is being fed frequently.
I personally usually offer a water dish to most of my slings, unless I am not able to fit one in their enclosure. It’s at this stage that they are most likely to get dehydrated due to the very dry, hot climate that I live in. I’m not worried about them drowning since they will also float on the surface of the water just like adults.
I use 9mm tattoo ink cups for this purpose, which are easy for most spiderlings to cross with the size of their leg span. The tiny size of these cups does mean that I have to fill up the dishes more frequently.
They usually are in a container that has plenty of room for a small cup once they’ve reached a ½” leg span (a 40-dram vial can accommodate a small cup easily).
For the ones where it isn’t practical to offer a tiny water dish because they’re in a super tiny vial, like my Hapalopus sp. Colombia when I first got it, I just drop a bit of water on their web or on a clump of sphagnum moss every time I offer food to make sure they have an opportunity to drink. I’m also careful to make sure that the lower substrate levels remain moist.
Both methods (water dish vs. no water dish) work perfectly fine, and I’ve raised healthy spiders using each one. However, I personally feel better with the extra security that a water dish offers.

Will a tarantula drink out of a water dish?
Yes, they absolutely will drink out of a water dish if you provide it! Although you may not have caught them doing it, tarantulas have no problem drinking out of a water bowl if they’re thirsty. I’ve caught tarantulas of all life stages drinking. Even my arboreal tarantulas will venture down to the floor of the tank for a drink when I fill up their dishes.
This is true for both captive-bred and wild-caught specimens. If you don’t give them a dish, they will drink from water that accumulates on top of the substrate, droplets on sphagnum moss, or anywhere else that the water has pooled on tank decorations and webbing.
Do I need to put a sponge in the water dish?
Adding a sponge to the water dish is surprisingly common advice that I come across, and I think people recommend it because they see pet stores doing it. Don’t put a sponge in your tarantula’s water dish.
Not only is this completely unnecessary because they can drink out of a water dish without drowning, the crevices in the sponge will potentially harbor bacteria. Keep it simple, just use a shallow water dish and don’t overthink things. Some people suggest using small pebbles in water dishes for slings.
You can do that if it makes you feel more comfortable, but just know that adult and juvenile tarantulas definitely do not need added pebbles or rocks in their dishes. They climb in and out of them perfectly fine.
Why don’t some people give their tarantulas a water bowl?
There are a variety of reasons why someone may choose to forgo using water dishes in their tarantula enclosures. For example, one argument is that they would only get their water from prey and rainfall in the wild. Therefore, they should be perfectly fine without a dish put in their enclosure as long as they are offered food regularly and a corner of the substrate is occasionally flooded so they can drink.
Another argument against water bowls is that they are unsightly, or that they are difficult to fit inside of the enclosure. I don’t personally have a problem with the way that ceramic bowls in neutral, earthy colors look in my tanks, but I can see why some people would feel this way if they are spending a lot of time creating bioactive enclosures.
That being said, having live plants in an enclosure that can catch water on their leaves is essentially providing the same thing as a water dish, and I think it’s important to point that out for new people that are reading the threads where more experienced keepers who keep planted enclosures are arguing against dishes.
I have also encountered people who argue that including water dishes is just adding an unnecessary step to maintenance and it’s more time consuming to keep them filled. The inability to stop tarantulas from covering their bowls with substrate, or to stop them from putting boluses and molts in them, is another very common reason why people choose not to add water dishes to the enclosure.
It can be incredibly frustrating trying to keep up with a tarantula that insists on throwing junk into the dish every time you fill it up. Or, alternatively, webs it up constantly which either buries the dish from use or makes it impractical because the web draws water away from the dish leaving it almost immediately empty again.
I have a few tarantulas whose borrows are like bottomless pits for water bottle caps. I have no idea how many caps one of my A. marxi females is stashing, all I know is that they disappear within a day or so of me putting them in the enclosure. They aren’t harming her and it isn’t worth disturbing her tunnels trying to remove them so I just let her tell me when she’s tired of the caps. Eventually, one or two will resurface when she decides to remodel her burrow and I take them out.
I’ve also seen new keepers post on forums that their sling died in the water dish. They tend to immediately assume that it must have drowned and often start threads warning people against using bowls. However, what is more likely to have happened is that the spider died of something else and it happened to be in the water dish at the time it passed. Oftentimes, glaring husbandry errors are apparent in the forum threads that get started warning people that slings can drown in a water dish.
Many keepers that have been in the hobby for years successfully keep their tarantulas without dishes and it is a valid style of husbandry. It isn’t impossible to keep healthy tarantulas without a water dish, and I got my start keeping all of my spiders without them. However, I do feel that it takes more vigilance and solid husbandry skills to successfully do so.

Why are some people adamant that all tarantulas always need a water dish?
The biggest reason why people are pro water dishes is…why not? There’s no compelling reason why a tarantula should not be offered something to drink out of just like any other animal being kept in captivity. Adults and juveniles will not drown in their water bowl. Even the tiny spiderlings are extremely unlikely to drown assuming they have room in their enclosure for one.
Keeping water available at all times means that your tarantula is less likely to die of dehydration like it could if it was being kept on bone dry substrate without a dish.
If someone is new to the hobby and doesn’t know how to regulate soil moisture well yet, or what to look for in a dehydrated spider, then having a water dish is like an extra insurance policy against beginner mistakes. This is especially true for slings because they lose moisture faster than adults.
If you’re trying to think of instances where this could be a problem, consider the logistics of accurately predicting when your tarantulas will molt every time. Do you always know the exact day when every single one of your tarantulas is going to molt? Probably not, even with record keeping. Otherwise, there wouldn’t be instances of tarantulas surprising people by molting in transit after being shipped.
I have always noticed my tarantulas drinking heavily right before they molt, which is one of the main reasons I prefer offering dishes. Tarantulas rely heavily on internal moisture to successfully molt, and I don’t want them to have complications due to dehydration when it’s something that I can easily prevent.
How do I water a tarantula without a water dish?
I actually learned tarantula keeping initially from someone who never used dishes and they were very successful at keeping spiders. For most species, they taught me to just flood a corner of the enclosure every so often, occasionally mist the webbing or sphagnum moss with water (especially during premolt), make sure food is being offered regularly, and to monitor the moisture of the lower substrate levels adding water if needed.
Misting the webbing or the moss wasn’t to increase humidity (your tarantula needs soil moisture, not a humid environment). Rather, it was done to pool some water so the spider could easily get a drink.
It’s important to keep in mind that the temperature and humidity in the room you keep your tarantulas will influence how often you need to moisten the substrate, and the ventilation of the enclosure will influence how quickly the top levels of the substrate dry out (which is desirable).
The substrate will look darker when it’s moist, and lighter when it’s dry. As a side note, flooding a corner of the substrate isn’t advisable without adequate cross ventilation. Enclosures should never be allowed to become swampy, and it is generally a good practice to allow it to periodically dry out.
The way that I learned how to keep tarantulas was a pretty hands off method that emphasized keeping things simple. I kept all of my tarantulas this way for many years with no problems, even arboreal species.
However, I started offering water bowls to most of them after watching a few of my spiders readily drink out of bottle caps. When I noticed how quick they were to use the dish I offered I couldn’t see a reason for not keeping one available if it was practical.
If you’re interested in not using a dish, then make sure you take the time to read tarantula forum topics that are discussing the care of that particular species to ensure you understand what kind of moisture they require, as well as the methods of providing moisture that people use when they forgo dishes.
What kind of water bowls do you use for tiny tarantula slings?
The best watering dishes for tiny tarantulas that I’ve found are 9mm tattoo ink cups. I bought a giant bag of these years ago for less than $10 based on a recommendation I found on Arachnoboards and I still haven’t made a dent in the bag!

I use them for both terrestrial and arboreal slings. Alternatively, if the enclosure is too small for a dish it’s perfectly fine to forgo one completely and monitor the substrate moisture until they’ve moved into a larger container.
When I opt to omit the dish for my really tiny terrestrial slings, I’m always careful to make sure I keep the lower layers of the substrate moist using a syringe. When the lower levels are moistened, but the top layer is allowed to dry out, the babies will dig down if they want the moisture. I don’t like to just pour water on the surface to dampen the substrate because it usually ends up pooling and I have had the pooled water flood a tiny tarantula’s burrow before it was able to sink into the substrate.
When I leave out the dish for really tiny arboreal slings, I’m always very careful to make sure I still keep the lower levels of the substrate moist (not soggy or mold growing). To make sure I maintain adequate soil moisture, I usually use more substrate than I see a lot of people use for arboreal slings.
I compensate for this with a slightly taller enclosure, and I typically mist their webbing lightly every time I offer food to make sure they get a chance to drink. It’s important to note here that I live in an extremely dry climate and that affects how I approach husbandry.
To use the tattoo ink cups, make a small depression in the substrate with the wooden end of a paint brush or just your finger. Then, push the cup into the depression so that the top is pretty level with the surface of the dirt. I sometimes attach magnets to mine to make elevated dishes for my arboreals.
If you can’t get a hold of 9mm ink cups, then you’re not out of luck. Aside from the ink cups, there are a lot of creative ideas for tiny tarantula water dishes. Some other options that people use include small seashells, single Lego pieces, blister packs from medicine that they’ve washed out, and tiny pieces of straws that have been hot glued shut on the bottom (then poked into the substrate).
How do I stop my tarantula from burying its water dish?
Good luck with that! You can’t stop a tarantula from burying its water bowl, or from putting boluses, poop, and old molts in it.
My arboreal tarantulas seem to be the worst offenders always dropping trash from their web hammocks into a fresh dish. My oldest C. versicolor seems to wait until I fill up her water to do her house cleaning, and she’s consistently done this for the past eight years.
Sometimes I stop offering dishes to the ones that repeatedly web over or bury them (like the ones that have at least 12 water caps buried in the depths of their burrows somewhere). When I do this, I make sure I pay careful attention to the moisture level of the substrate when they are nearing a molt while ensuring that they get ample opportunities to drink.
However, most of the time I continue to add a new water bottle cap every time I do maintenance if the previous one has disappeared. If the old one is buried or otherwise impossible to extract from webbing I just wait until the tarantula removes it for me. It isn’t worth stressing over, and the spiders don’t seem to mind either.

How often do I have to refill the water dish in my tarantula enclosure?
You don’t have to be super strict about when the dishes are refilled. The frequency that you have to top off the water will depend on varying factors in the environment, like the temperature and humidity in your spider room, what kind of substrate you use, and if any of the tarantula’s webbing is touching the water dish.
The size of the water dish will also affect how often it needs to be filled. If any webbing or substrate is touching the rim of the bowl the water will get wicked away rapidly. Just check the dishes whenever you’re doing any cage maintenance or offering food. On average, I refill mine 1-2 times a week.
Whenever I feed everyone, I’ll go through and top up the water dishes, and I completely replace or wash the dishes when they start looking gross (like when a tarantula drops a food bolus in it). Always make sure you fill up the water dish if you plan on being away for a few days.
Keep in mind that premolt and newly hardened post molt tarantulas need water the most at these times. Tarantulas that are in premolt will readily accept water because they need the internal hydration to successfully shed their old exoskeleton. I always refill the dishes if I notice that any of my tarantulas have recently molted because they lose a lot of moisture in the process. This is why you will sometimes see them chewing on a fresh molt.
What’s the easiest way to refill the water without spooking my tarantula?
The best tool I’ve found for watering tarantulas is a soft plastic squeeze bottle with a long, curved spout at the end. Using something like this makes it super easy to refill a dish or moisten the substrate while being unobtrusive to the spider.
You can also simply pour water in carefully with a water bottle, or use a syringe/pipette for smaller water dishes. I don’t like to pour water directly from a water bottle because this usually does spook my tarantulas even when I’m trying to be slow and methodical about it. The curved spout on the squeeze bottle I use lets me direct the water exactly where I want it to go, and it doesn’t make any alarming rushes of water.
If you aren’t using a water dish, a syringe with a metal tip is the easiest way to moisten the lower levels of the substrate thoroughly without flooding any burrows or making the water pool on the surface. Just make sure you release the water slowly allowing it time to soak into the substrate before continuing.

What kind of water dishes should I use for my adult spiders?
Water bottle caps make excellent water dishes for tarantulas, I always keep a stash in a jar for this purpose. So do lids from juice bottles and plastic jars. I use tiny ceramic dishes in neutral browns and tans for my largest tarantulas that I think were intended to be used as hamster food bowls so that I can keep the enclosures aesthetically pleasing to look at. One unintended perk to using ceramic bowls is that they are too heavy for the tarantulas to flip over.
Do I have to offer a water dish to heavy webbing tarantulas?
You don’t have to keep putting in new dishes if your tarantula just keeps webbing over them. I will sometimes decide enough is enough if their web fortress gets to the point where it looks like I’m just showing off a bottle cap castle. The spider will still be able to get a drink from the water that pools on the webbing just as well as they would from a bowl if some water is dropped on the web during feedings and other maintenance times.
Alternatively, you can try using a larger or heavier water bowl that’s harder for the spider to drag or tip over. This makes them less likely to add them to their web creations. I don’t ruin webbing to remove buried dishes that are firmly incorporated into the web. For the most part, the only ones that give me trouble with this are the spiders that prefer dry conditions anyway so I don’t think they mind getting their water from a web puddle.
How often will a tarantula drink water?
There really isn’t an answer to that question because they will simply drink when they need water. This will vary depending on the temperature and humidity in your environment, the moisture retention capability of the type of substrate you use, how often they’re fed, how close they are to a molt, and the species that you’re keeping.
I most frequently see my tarantulas coming out for a drink after they’ve molted, and I also notice them drinking a large quantity of water in one sitting right when they’re in heavy premolt. So, these are the times that I’m particularly careful to make sure that they have water available.
How long can tarantulas go without water?
The tolerance for drought will depend on the species that you are keeping. The temperature and humidity level in your tarantula room, as well as the size of the spider and your feeding schedule, will also influence how long they can go.
In general, a tarantula can go without food for much longer than it can go without water (so if your tarantula is refusing food make sure you keep offering it water). If you’re just going on vacation for a week or so your spiders will be fine. Just make sure they’ve eaten before you leave, moisten the bottom layer of the substrate, and leave a water dish for them.
If your spider has webbed up its hole or its hammock and is refusing water by its own accord just leave it alone. It will be fine. If it has been holed up for a particularly long time you can moisten a corner of the substrate occasionally for terrestrials, or drop some water on the web for arboreals. The spider will still get the water that it needs if it wants it.

How do I know if my tarantula is dehydrated?
A dehydrated tarantula will have a smaller than normal abdomen that appears sunken or even shriveled. This is something that I commonly see in Arizona when I find mature males out roaming at the end of the mating season. You may also notice a dehydrated spider acting sluggish.
Depending on how long they’ve gone without water, they may also start going into a death curl which can present in various stages of the pose. A death curl is where the legs curl underneath the body, not to be confused with the position they molt in (which is on their back with their legs curled on top).
How do I rehydrate a dehydrated tarantula?
If the tarantula is only showing signs of a shriveled abdomen or is acting sluggish, then the only thing you need to do is offer them a water dish. Your spider will take care of the rest. However, if the spider has gotten to the point of being too weak to move, but they are still alive, then they will physically need to have the water placed near their mouth.
This can be done carefully with a pipette after the spider has been turned on its back, or by placing them on top of a water dish so that only their fangs are exposed to the water (never place a sick spider’s abdomen over the water because this is where their book lungs are located).
It’s important to note that care should always be taken when you’re interacting with a tarantula this way. Even dehydrated ones still have venom and can bite. You will have to make your own judgment call as to whether you’re comfortable doing this or not.
I found my tarantula upside down in its water dish. Is it dead?
If your tarantula is upside down, then it’s trying to molt in its dish. Do not touch a molting tarantula, blow on it, or try to pull it out of the water bowl. It may not survive the molt if you do. If you are worried that the water level is too high, then the most unobtrusive thing you can do is to use a pipette to carefully suction out the water from the dish without touching the spider while you’re doing it.
I’ve seen quite a few posts over the years on tarantula forums where people say that they quit offering water dishes because their tarantula drowned (or could have drowned) because they found them on their back molting in the water dish.
Although this seems to be a pretty common occurrence on tarantula boards, it isn’t normal behavior for a tarantula and it suggests that something isn’t right with their enclosure. If a spider is trying to molt in a water dish, then you should take a closer look at your husbandry to ensure you are taking care to offer them opportunities to drink while in premolt and meeting their species-specific moisture needs.
Is it safe to wash a tarantula’s water dish with soap?
Adding a surfactant to the water will break the hydrophobicity of the tarantula’s exoskeleton, which can certainly lead to a spider drowning. If you’re going to wash out your water dishes, especially in sling enclosures, make sure that there isn’t any soap residue left behind. I have read several forum threads where people suspected that soap residue was left in the tiny water caps causing their slings to drown.

Final Thoughts on Tarantulas Drowning in Water Dishes
If you’re brand new to keeping tarantulas, then I would always recommend using water dishes even for slings. Just use something that makes sense in relation to the size of the tarantula. While I don’t believe that using water dishes is a necessity, I do think a lot of beginner husbandry errors can be prevented by offering one.
However, if you already have a handle on tarantula keeping, then you could go either way after reading everyone’s opinions. I’ve kept tarantulas with and without water dishes, and my preference these days is to offer one by default.
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