# Ruminations on ventilation



## piquete

Caveat reader: I'm a newbie. I'm just tossing ideas, don't take this as a recommendation of any sort. I'm asking for opinions and not advocating for the use of a particular setting.

I've been thinking about the quality of air in Piquete's tank (new pics!). Many pointed that air quality isn't the best in such an enclosed setting, so I started thinking about some physics.

First of all: the upper opening is huge.

Second: gas concentrations don't vary too much in an unrestricted setting like that. The difference in oxygen concentration vs the surrounding space should be negligible.

Third: this only applies if you use a "spot" heater such as a lizard pad (me), a snuggle safe disc or anything similar. Hot air rises. Convection causes cooler air to be "sucked into" the tank, to refill the empty space left by the now gone hot air. This effectively creates a draft that renews the air always sucking "new" air form outside.

Now the fun part: am I crazy? Are objections to tanks a matter of tradition or there's more to it that the -seemingly unaffected- ventilation?

I'd love to know what you think.

Best,
Andres

PS: Pic!
[attachment=0:2qjr3ut0]IMG_02822.jpg[/attachment:2qjr3ut0]


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## amanda

Sorry this is going to be long...

1. An issue with tanks is that they do tend to retain odor which is kind of gross, but if you are willing to go the extra mile to clean it everyday to prevent any type of bacteria from breeding, then you shouldn't have an issue with it affecting your hedgie's health.

2. Your thoughts on


> Convection causes cooler air to be "sucked into" the tank, to refill the empty space left by the now gone hot air. This effectively creates a draft that renews the air always sucking "new" air form outside.


 It doesn't quite work that way. The only reason it gets cooler is because the warmer air particles are moving faster and want to create an even temp in all surrounding air particles. Therefore they spread out and the air cools. There is no circulation of the air unless you have something that is circulating it. It may not stay as concentrated, but remember that glass is a really great conductor of heat. So, it is also storing heat that is given off by your heating element. I hope that makes sense, it has a lot to do with physics. I can explain further, it would just take awhile... you may pm me if you have any more questions.

3. You do have to worry about humidity in a tank, which if not monitored could lead to an upper respiratory infection.

4. There is nothing wrong with using a tank as long as you are willing to do everything you need to do to keep it extra clean. I would just make sure there is good circulation in the room you are keeping your hedgehog in, but no draft. A draft and circulation are two different things. Drafts are notorious for causing problems. Most people find tanks to be more hassle than they are worth.

I hope that all made some sense.

-Amanda


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## HedgeMom

Ammonia is heavier than air. As long as your hedgehog is excreting, the air quality at the bottom of that cage is going to be poor.


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## knitfreak

You know, I had a bunch of questions about this when I first got on this forum! I can't see the difference between this and the bins everyone uses. Some people say the bins are larger at the top than the bottom, but if the physics above are true that that really wouldn't matter anyways, would it? I clean my hedgie cage every morning, so at most he has 6 hours where there *might* be smell. It's not like you're accumulating a weeks worth of waste at the bottom of a dark tunnel. :lol:

From my experience - they are not too heavy to clean. I have my hamster in a 20g long aquarium and it's quite light. I have no problems cleaning it and think it's easier to clean than barred cages. I bring it to my sink, add water, wash, rinse, then wipe dry. It takes about 5-10 mintues for an entire cage clean 

For the circulation, my hamster seems fine. I clean her little pan more often than the rest of her cage, but it's not stinky that I can tell. As far as I am concerned, aquariums are great for hamsters! 

I don't know about hedgehogs, so I got the barred cage that was suggested to me. Heating is a horrible issue though, it's really difficult to keep it a consistent temperature. Walking by it causes enough air to move for all the warm air from the heater to just dissapate. I am thinking I will have to add another 150watt bulb before winter really hits, and even then the best option at this point is to MOVE to a new place!!! I am not in control of the apartment heat, and it's set for human standards.


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## nikki

The ventilation difference between a bin and a tank are that people that use bins drill holes along the sides down near the bottom and sometimes up the whole sides, for better air movement.


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## knitfreak

Some people do, I've seen a lot of bins without the holes though. Even still, a bin isn't going to have that much more air movement over an aquarium! Unless you have a fan nearby or something - according to the physics above anyways.


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## Nancy

Even a bin without holes drilled offers better ventilation than an aquarium. Bins are usually larger than aquariums and their sides slant up which gives more surface ventilation. Tanks are usually tall and narrow whereas bins are wider.


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## knitfreak

Well, my 20 gallon long aquarium is more shallow than anyone's bins are. It's only 12 1/2 inches high. It would depend on what type of tank you have. It looks to me like the tank that piquete has is roughly the same height as bins, you can tell from the wheel height.

Amanda, what are your thoughts on the surface ventilation? If what you say is true about the air not really moving then it seems like it wouldn't matter about the surface which is over a foot from the floor of a bin - or an aquarium.


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## amanda

A bin and aquarium are essentially the same thing in regards to surface ventilation. The sides being sloped makes a small difference in ventilation. A lot of bins do not have enough sloping to make a valuable difference. However, this being said, when people add holes to their bins to increase air circulation and ventilation in their bins it does help tremendously as long as they have open topped bins. The physics below was more in regards to heat, and how it diffuses through the air. You will still have no air circulation if you do not have a fan or a/c or something that circulates air through the room (common sense, it is why a parked car gets hot and stagnate* in the summer)

*stagnate: cease to flow or move; become stagnant. • figurative cease developing; become inactive or dull

If the open surface area at the top was smaller than the surface area at the bottom, then you would have an issue with air becoming trapped. 

I personally do not think that the bins without holes offer much more benefit than an aquarium. They have the same basic physics in regards to air flow. 

Other factors that push people to use bins over tanks:
-cost
-weight
-ease of cleaning (for some, a 10 gal tank is way diff than a 150)
-the bad stigma associated with tanks
-availability
-Easy to modify (add ventilation and can connect with others easily)
-much more difficult to break

You should technically be able to use any hedgie safe enclosure as long as you are a competent owner and are willing to do the extra things needed when using said enclosures. If you do find that you hedgehog is not flourishing in its environment, it needs to be addressed immediately. This being said please make sure you are making the best decision for your hedgehog and not for your own convenience. 

As for excrement, like I said before if you are willing to clean your cage more often you should be fine. Also, if you use a more absorbent bedding that helps absorb and remove odor, it should eliminate a lot of the issues with your hedgehog breathing in his own excrement (the ammonia from urine).

SIDE NOTE: Using a tank is not comparable to sleeping in a port-a-potty or anything like that. (yes I have heard this reference used) I find it offensive for people to make rude comments like this, so please leave non-constructive comments to yourself.

Was that long or what??? 

What I use: I use barred cages, I find them very nice and I have never had issues with them. I like open aired cages because it allows for much more ventilation and I prefer the aesthetics. I like to color coordinate. Purple cage, purple wheel, colorful fleece liners!

-Amanda


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## knitfreak

Thanks Amanda, that was really helpful. 

One more thing I was thinking of - for rodents tanks are much preferable over bins because plastic reacts to their urine. Anyone who has had a hamster, rat, mouse, gerbil, etc, can attest that in a plastic bottomed cage the pee corner gets HORRIBLE within a month or so, depending on the type of plastic. That is why mine is in a tank (well, that and the incessant chewing.... ugh!). I'm not sure how hedgie pee is with plastics.


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## HedgeMom

I do think using a tank is comparable to having a hedgehog sleep in a portapotty. Especially if you use KD pine shavings, which release VOCs when in contact with ammonia. 

I suggest you test this. 

Put 2" of shavings in the bottom of your bathtub and close the sliding door. 

Spend the whole day peeing and pooping in the tub. 

Make sure you lay face down and keep your nose within 1" of the bottom of the tub. 

Lemme know how that works for you. 

Repeat, leaving one side of the shower door open. 

Report back.


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## Anny

I think the comparison of a tank to a porta potty is a bit much and pretty darn harsh... It's posts like this that almost made me turn around when I first got here... It's one thing to want to educate others and a complete other ballgame to be just plain rude. 

Just the comparative size of a human in a porta potty versus a hedgie in a tank can't be compared...

I get the point that aquariums have poorer ventilation but I've seen plenty of bin setups that didn't have ventilation holes at all and had pitiful floor space to offer. I really can't see why a decent sized tank is worse than a small bin enclosure.

Having experienced trying to keep a hedgie in a large tank (36 gallon), I learned pretty quick that it wasn't the best set up for me and my hog. Even if it was large enough in my opinion to offer decent space and adequate ventilation with daily cleanings, in the end I wanted something bigger and more practical. 

That doesn't mean I think aquariums are total crap, just that they are much more of a pain than other types of enclosures to deal with. If someone has a big tank and wants to keep their hedgie in it and bust their ass cleaning the thing out daily: knock yourself out with that! lol 

With all that said, the size of the tank posted here is way too small in my opinion... When I see how much my girls run around their cages besides how much they wheel every night, I can't imagine having them in anything that small!


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## LizardGirl

IMO any glass tank under 40 gallons is too small regardless. Once you get larger than that, the floor space is much wider which can help, but still isn't ideal. 

With aquariums, you would need to circulate the air to keep it from getting disgusting, and that draft would likely cause hibernation.


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## amanda

I made a comment about the port-a-potty thing to keep that kind of thing off this thread. There is someone on here who likes to make that comparison instead of trying to be constructive. I'm sorry if you misunderstood what I said. But, thank you for reiterating my point. Comments like that are non-sense and need to be left out.


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## knitfreak

To compare an aquarium to a porta potty is silly and pointless. If you use liners and clean the cage everyday what the real equivalent would be is a child peeing their bed and having the parents clean it in the morning. Hardly abusive! :lol:

Like I said before, my hamster (who has piss that smells far worse than my hedgehog) is in an aqaurium and it does not stink. I do not need to add any extra circulation than the normal air currents in my room. If you clean out the pee and poo every day, what is the problem? Again - no different from a bin.

As far as floor space goes, a 20g long has over 3 feet of floor space, so according to the recommendations on here it is big enough. A 40g (36"L x 18"W) has over 5 and a half feet of floor space. So that is pretty big hedgie cage by most standards with lots of extra room. The recommended minimum amount (from this forum) is 3 feet, or at least 2 feet left over after adding in the accesories and wheel, etc.


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## Nancy

I tend to agree with the portapotty comparison and a bathtub with the doors closed is a perfect example. 

Most people who use aquariums are talking about 10 & 20 gallon ones and to keep an animal the size of a hedgehog that poops as much as a hedgehog in one of them is cruel as far as I'm concerned. One night of pooping and that thing is going to stink like crazy. Even cleaning it out daily the hedgehog is still going to have to put up with that stench the whole night when you consider that they start to do their business within about 15 minutes of getting up. 

Consider how many people totally clean their cage daily? Very few do. Most people clean every second or third day and look how many people we see on here complaining about the smell and they are only cleaning once a week. If this is an aquarium, well there's your living in a portapotty scenario. 

Now lets consider individual hedgehogs. Some have very strong smelling urine. Babies all do and some adults. My Smokey (RIP) was horrible. He needed his cage cleaned daily. Thankfully he used his litterbox to pee in so he was an easy daily clean but his fresh urine would smell up the whole room and he was in a well ventilated cage. Imagine this in a closed in aquarium.  

The 30 gallon plus aquariums are not a bad size as far as floor space but still, they tend to trap the odors at floor level where the hedgehog is living. In looking at my daughters aquariums, 33, 40 and 90 gallons, the only one I would consider putting a hedgehog in is the 90 gallon that her turtle is in. It's a good size but cleaning would be difficult as it takes 2 people to lift the thing. 

I guess I don't understand the point of using an aquarium when there are so many better and healthier options. I also don't understand the point in arguing for aquariums when those doing the arguing don't even use one. I don't think anyone can argue the fact that between an appropriate sized plastic bottomed/wire topped cage versus an aquarium, the wire cage wins hands down in being the most healthy, convenient and practical choice for any small animal. There are many breeders who will not sell to those planning to use an aquarium or a bin.


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## hedgieMate

I’m not 100% sure if the port-a-potty analogy is completely irrelevant and pointless either. I might be wrong, but the point of the analogy seems to me that forcing any animal (including human) to live in an ill-vented small space with his own waste on the floor isn’t a good idea. If my understanding is correct, it strikes me as a legitimate comparison. Analogies such as this often are used to emphasize the point of view so that readers/listeners can instantly get the idea.

For the sake of argument, let’s say the port-a-potty had 10 times the floor space. Would you want to live in this enclosed space even for one day? Especially if you had to walk on all fours keeping your nose close to the floor at any given time? Oh, let’s not forget you wouldn’t have a septic tank in which your waste gets collected and contained away from the area where you lie down in or where you eat food. Rather, your waste is scattered around on the floor of this ill-vented enclosed space at least for 24 hours before the next clean-up while you eat, play, and sleep. You might be able to bear with it for a day or two, but would you live in the space day after day for many years?

To me, there are a few big differences between aquariums and large plastic bins. First, aquariums are made of thick glass. The heat transmission/conduction of glass is quite different from that of plastics. If you use Pyrex pots and pans for cooking, you would know this. Glass takes a LONG time to heat and, once it reaches to a certain temp, it retains the heat longer than metal or plastics. What does this translate to? Well, during the wintertime, glass will stay relatively cool to touch even if the room temp is kept warm enough for hedgehogs. Glass will constantly draw heat from your hedgie's body, like you lying on a tile floor; even if you had a blanket, your body would feel cold because the tile floor constantly draws your body heat and spreads it to the other part of the floor to even up.

This very same nature of glass leads to a condensation problem as well. Since glass has a higher thermal mass, urine remains in liquid form (rather than dries up in a well-ventilated plastic bottom wire cage) and tends to create condensation which could lead to mould and possibly to respiratory health issues in your hedgehog. In other words, the condensation problem in an aquarium is not solely created by poor air circulation. It has a lot to do with the material that makes up the box. Needless to say, plastics doesn’t have the same problems.

I also believe that good air circulation is created by cross-ventilation. A air system that relies on a one directional “opening” is not adequate. Thus you must drill holes in a plastic bin to create cross-ventilation if you choose to use a large enough plastic bin as a hedgehog habitat. Multiple ventilation holes create cross-ventilation and keep the space within well-ventilated, even without a fan. Even in a closed room with no ceiling fan, there is almost always convective air movement due to differences in temperature. It's just most of us are oblivious to this fact since the air current is so minute, but otherwise you would feel stuffy in the room. You don't feel stuffy in the room because the room is adequately vented - and this is not the case for the aforementioned port-a-potty. And to vent a room adequately, you require cross-ventilation - you must create a path for air, not just an opening to one side (if you keep the door to the port-a-potty open, you have less of a ventilation trouble, for instance, because there is more cross-ventilation, see?) 

Aquariums fail to provide sufficient openings to create adequate cross-ventilation and the resulting air movement; they are much more restrictive than a plastic bin with holes. Thus aquariums make a poor habitat for most small mammals, in my personal opinion.


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## Anny

Sigh...

Porta potty: a VERY cramped area where one does not have the space to do anything other than pull their pants off and sit + turn around. Item whose SOLE purpose is for people to pee and crap in.

Aquarium: Enclosure many times the body area that said animal takes with an entire open top. Area has enough space for sleeping area, wheel, dishes, toys, etc on top of extra floor space. YES animals will also pee and poo in this area on top of many other activities.

It is still beyond me why some find this comparison appropriate... I truly find it mind boggling!!!

For the record:
I do agree that tanks have poorer ventilation than other types of enclosures. BUT, with a very good upkeep it can be worked with. Proper daily cleaning along with a couple spot cleanings each day. Otherwise it will get smelly and unpleasant for both owner and especially the hedgie.

Most tanks are too small. Same goes with most cages on the market! You can't buy something that has less than 2' floor space and expect a hedgie to be content in it, this is regardless of what the enclosure type actually is. 3' floor space is the minimum needed, and minimum is a key word there.


Having recently experienced different enclosure types, including an aquarium, I still don't see why there is this intense hate campain against them. They have a LOT of cons, but as with anything, the behavior and responsibility of the owner is the most important factor. Yet a lot of people here will ignore that and seem to almost enjoy making owners feel incompetent and bad about having one.

All I'm trying to say is that with a large enough tank and with an owner who is up to the task of keeping it clean enough, try and cut some a bit of slack okay? By all means go ahead and suggest something that can be easier or "better", just don't make people feel horrible and like bad owners for doing it the aquarium way if they choose to.

My final 2 cents on this debate


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