They're about 4" I've got a mix of very fine, maybe a size or two above sand grain sized gravel and small round pebble natural gravel. Most of it was out of 29g I took down and I added an additional 15lbs of the very fine grained stuff I got at a LFS. The only issue is it's white. It's all I could find in fine grained these days. It won't be white for long. LOL. I'm not sure the sad looking amazon sword will make it. It was buried in java moss in the 29 for a few years. It's never seen a root tab, ferts, etc.
That is interesting about the 50degF thing. I wondered for years what the basis of this was. When I asked a LFS if he had them or could get them, his reply was, he agreed it was odd he hadn't seen them in years and he for sure would put them on his next order for me. He called me a few days later giving me the no-go info.
I did mail order them. This was my first live goods mail order and I couldn't believe how smooth and easy it was. I also couldn't believe they'd ship to where I live given it's winter. They shipped out on a Wednesday afternoon and were at my door at 1130 on Thursday! The heat pack, packed in with them was still warm. My bride and kids are kind of invested in these little guys now too because they did the unpacking and introduction for me as I was at work. Per my panicked instructions over the phone of course. LOL
Without actually asking I can make an educated guess on the 50 degree threshold, and I suspect it has to do with what temperature a fish reaches torpor and how long it can survive while in a torpid state below that temp. A fish doesn't just die in minutes at certain temperatures. Rather, a fish will gradually slow it's metabolism as temperature decreases until it reaches a near hibernation state, called torpor. If water temperature continues to drop, eventually the fish will reach a temperature that it can't withstand, it's body just shuts down completely, and it dies. Goldfish and temperate fish go into a torpid state at a much lower temp than tropicals, and can withstand temperatures that are near freezing. I'd guess that most tropicals reach torpor at a temp somewhat higher than 50 deg, and can't survive long term in water much below that 50 deg threshold while in a torpid state. If they can't survive they can't become invasive. I know waters here in Wyoming often get close to freezing and below 50 deg is a given in the winter, so the risk of a tropical becoming established as an invasive species is virtually nil. The risk of a non-native species from a temperate or even a sub-tropical area is much higher though because of a lower temperature threshold for death in cold waters, so these species are illegal to keep. I looked at where you're from, and I guess that water temps are similar in New York in the winter.
There are two tropical species established in Wyoming, however. Swordtails and convicts have established themselves in some hot springs in the northwest corner of the state, south of Yellowstone National Park. They, as well as guppies, have established themselves in a couple of hot springs in eastern Idaho. I read about a pond that is fed by a hot spring in Idaho that had swords, tiger barbs, convicts, and a species of tilapia in it that had developed it's own, stable balanced ecosystem. This is actually a problem, because hot springs already have they're own micro ecosystem and the addition of fish destroys or alters this. Some of these hot springs have microorganisms that only live in that one spring, so altering the ecosystem risks destroying entire species.
WYite
