HCA: Hermit Crab Association

(I wasn't sure if this was supposed to go in Crabitat Conditions or DIY, so sorry if it's in the wrong place... ^^; )

I currently have two medium/large PPs in a 10gal tank. It's getting a little crowded in there, though, and I'm not all that happy with the current setup. So I went and bought a ~20gal tank (2' long, 1' deep, 1.5' tall). Unfortunately it's from thrift store, so it has no lid. Since I have to make lid for it anyway, I figured I might as well go all-out and customize the whole thing with a built-in freshwater pool and a light hood and all that. ---I bought a lid and am doing removable filtered pools instead.--- However, this is the first time I've ever customized a tank, so I have NO IDEA what I'm doing. So I'm just gonna post some questions, and answer whichever ones you can. Thanks! ^^

Lid:
-What materials should I use? I like the circulation of wire mesh, but the humidity-retention of glass/plexiglas--any ideas on good ways to combine them? Also, where the heck would I buy wire mesh and plexiglas?
-How do I incorporate a light hood? What kind of barrier should there be between the tank and the light?
----Does anyone have light hood suggestions? I really like this combination hood from ZooMed (holds up to 4 incandescent lights and 1 long fluorescent), but it is REALLY expensive. Something like this would also work, but I can't find one that has independent control of all three lights.---
-What types of lights ---wattage--- should I use in the light hood? (It can get very cold where I live, down to 40-50°F in my room when the gods of the steam heat system are feeling perverse, so I definitely need something that can put out a fair amount of heat in the winter)

Freshwater ---and saltwater--- pools:
-What type of sealant should I use?
-How big/what dimensions should the pool be?
-I'd like to put a filter and bubbler in there to keep the water clean and aerated. What brands would you recommend, and are there any good, small filters that can double as bubblers? ---I'm considering the Koller Craft Dive Clean Mini Filter. Opinions? Anyone have experience with this filter?---
----Can I use this type of filter in a saltwater pool too?---
-What's the best way to keep the filter/bubbler out of reach of the crabs?

I was also thinking of doing a DIY humidifier, but the picture on the Bundy humidifier thread is broken and I'm a little confused how to put it together without pics. Does anyone else have pics/instructions for their own DIY humidifier?

Any other tips or suggestions from veteran tank customizers would be greatly appreciated.

I don't know how you'd do heating with a hood - all the hoods I've seen at pet stores fit fluorescent lights, which don't give off much heat. I've heard of a reptile hood which can heat the tank, but I believe it's rather expensive. For my 55g tank, I have a mesh lid with pieces of plexi-glass on top (so if I want more ventilation, I can just move the plexi-glass over) and for heat/light I have two clamp lamps and a ceramic heat emitter. My dad built a fixture out of wood to clamp the lights onto. It works pretty well overall. Also, if you have a normal sized tank, you should be able to find a mesh lid that will fit it - my tank didn't come with a lid either, but I found one at a nearby pet store. Here is a pic of my set up:



As for the bubbler, I used to have one...I hooked up the air pump, air tubing, and air stone (you can find all of those at a pet store) and took a little glass jar, filled it with some glass rocks, and stuck the air stone in. Just beware that your crabs may try to climb up the air tubing...most of my PPs never managed to get very high up, but when I got E's, they would always climb to the very top and crawl around upside down on the mesh lid.

Anyway, good luck with everything! Hope this helped a little.

I'm not going to be of huge help here, but here is what I do know:
When I had a 20g, I bought one of those wire mesh screen things that was specifically built for 20gs. I got this at Petco. Then I bought some Plexiglas and cut it down to size so it covered about half of the tank. with the other half, I just used a regular tank hood light. The mesh/wire had a coating on it so it never rusted. I never had a problem with this setup.

I know little to none on the topic of sealants, but I think some people have used aquarium sealants?

I know you said about heating. I have always used a uth, but thats just me. I now a lot of people who do something Tremors did. I think if you search, there have been some topics on the different types of heat lamps, including ones to use at night.

Good luck!

Okay, I'll see what help I can be as I too have a long 20 gal. I second the idea of combining the mesh and plexi, you can get plexi (& have it cut) at a place like Lowe's or Home Depot.

I too use the clamp lights, but I clamp it to the side of the tank since I have old house windows for a lid and having it on top cracked one of them.

As to your pool, I have heard that built-in pools are a pain to clean, but you can use aquarium sealant to do it. However , my PPs, DON'T like deep pools. I have talked to a lot of other people & they said theirs don't either. If I put a pool in that has water more than an inch deep; they won't go in. They will drink & maybe even dip a foot, but they don't wade in.

I have some good instructions for a DIY humidifier (I have one in my 20 right now) that someone else made me; PM me & I can email you the directions. It costs less than $15 to make & is good for up to a 50 gal tank!

Update: upon further consideration, I've decided not to do the built-in pool and just use a large tupperware setup instead. However, I would still like to have a filter so that I don't have to clean it as often. The one I bought is a small (filters about 20g I think) TetraFauna ReptoFilter. I really like it because it spills out the filtered water like a fountain and can operate in only 2-3 inches of water, but it's pretty large for the size pool I had in mind. I was thinking maybe a Koller Craft Dive Clean Filter instead? Does anyone have any experience with these? And can water filters like these be used in salt water too?

I did buy a mesh lid, but still haven't figured out the lighting and I couldn't really find a helpful thread. What bulbs should I be using for day and night? Basking or daylight? Infrared, red nightlight, or blue moonlight? I don't even know what the differences between all these bulbs are, much less which kind I should use...
And when paired with a UTH, what wattage should the day/night bulbs be to keep the tank warm? I looked at this equation, but it doesn't take into account a UTH or temp fluctuations outside of the tank. From looking at the equation I guess I would need something around 50 watts maximum for really cold nights, but then I don't want them to roast when it isn't that cold. >_>

For the fixture, I would really like to use a light hood rather than several separate lamps because I have limited space and will have to move the tank around occasionally. Something like this, but hopefully smaller and less expensive. Can anyone suggest a hood that can hold 2 incandescent bulbs (of whatever wattage is appropriate for my tank...)?

I can't help you with the filters or the hoods, as I've never used either with crabs. However, here's a bit of info on some kinds of bulbs you might encounter:

1. Day-glos or daytime incandescent reptile bulbs- these typically both heat the tank and produce UVA light. They work pretty well, but they can be kind of expensive - usually $10-15 a bulb and they typically last a few months.
2. Fluorescent UVB bulbs - these do not really heat the tank, but they do produce UVB, which in some animals is important for making vitamin D. Look up any particular bulb before you get it, because there was one (don't remember which) that only projected the UV light about 2 inches...not much good unless your crabs can get to the very top of the tank. These bulbs are typically more expensive, but they last a while. (You're supposed to replace them every year.)
3. Regular incandescent light bulbs, like you'd use in your house - these can work well for heating, but they don't typically produce any UV light. The main benefit is that they are much less expensive than the reptile heat bulbs. I like to use one of these plain bulbs for heat in combination with a UVB fluorescent bulb.
4. Moon-glo bulbs or purple nighttime incandescent reptile bulbs - these are great for nighttime use. They produce very little visible light, but enough so that you can see your crabs. Unfortunately, I can't find them in anything higher than 75w, so I had to switch to a ceramic heat emitter last winter. Don't get these bulbs confused with normal black lights; some black lights produce UV light, and since quite a few invertebrates can see UV at night, this may possibly disturb your crabs.
5. Red incandescent reptile bulbs - these are okay for nighttime use with crabs also (generally, any light made for nighttime use with reptiles will be fine for crabs). However, the red lights seem brighter than the moon-glos...I had one at one point, but I sleep in the same room as the crabs and the light really bothered me, so I vowed to never get one again.
6. Ceramic heat emitters - these do not produce light and they get pretty hot. However, they are good for heating and usually last a lot longer than the incandescent bulbs. They also come in higher sizes than some of the other bulbs (mine is 150w).

To regulate how much heat goes into the tat, they have what I think are called proportional thermostats, which will help keep the temp about right. I don't know much about those - haven't actually gotten one yet. Also, the exact wattage you need depends on your own conditions - there's no surefire way to tell except to try it out.

Sorry if that was kind of long, but I hope it helped.

Thanks, that's really helpful! ^^