Heater for small shedding aquarium

[bnorthup]

I took 5 crabs from Lake Pontchartrain and put them into a 30 gallon aquarium on my back porch. I put a 200 watt aquarium heater in with the crabs. I found that the 200 watt heater was not adequate at all. The outside air was about 55 degrees. I put the heater in and it could only raise the temperature by about 5 degrees. There was just too much heat loss from the sides of the tank........   I may just give up this whole concept and wait for the weather to warm up.

[R D]

If a 30 Gal tank is all you have why don't you put it inside and then the water temp. will stay at room temp., 

[bnorthup]

I was sort of thinking that if I did that, then each crab might become sort of....... a pet, then it would be wrong to toss them into the boiling water, etc. These guys will just have to learn to fit into the overall scheme of things outside..........The economics must also be right. They cannot become a drain on the family economy.....   I ain't buyin' no air conditioner to keep crabs comfortable............   I'm gonna eat 'em and it ain't gonna cost me nothin'........   That's the way it's gotta be.

[jeff l]

Bill, one way or another they will cost you time or money the other thing, is the temp. might be rasied if you had less water in your aqaraum, I dont know if you have it filled all the way.

[bnorthup]

I don't mind the time part. I got lots of time. It's the money that is harder to come by. I actually WANT to spend my time messing with the crustacean type creatures.....   Your point about the depth of the water is a good one. The water was about 12 inches deep. Also, if there had been some insulation of ANY sort it might have allowed the temp to raise by maybe 10 or 12 degrees and this would have probably reached 70 degrees. Is that the magic temperature?...........   I'm haulin' them out of the water again this weekend for more inspections and experiments.
    I didn't mention that I had a large solar oven in the back yard. It is about 5'x2'x3'. On a sunshiny day it has reached 175 degrees when the outside temp is 50 degrees........   If I was really industrious I would rig up something......  run copper tubing through it or something.

[jeff l]

I thought I read 72 b/c if it's to high, the oxygen is depleted, also try an icechest to put the crabs in.

would you put the copper around the tank or in the tank? b/c I think copper would definitely kill them.

[bnorthup]

If I was to pursue the scheme of solar heating the "crabinskis", I would keep the copper away from the aquarium water.........   I am not committed to this YET.   These crabs are suddenly getting very uppity. I might just loose my patients altogether and commence to have BBQ male crab.
    At night the solar heater looses all heat output. In daytime it gets scalding. I would have to figure out how to average the heat so that it makes the water a constant 70 to 80 degrees........   Or I could just put them in the canal when the canal is the right temp. (most of the time)