In the topic of caring/feeding of a blue linkia starfish the posts expanded to their deterioration and subsequent death. I would like to add some info that may help persons with their invert pets, this info is from my own experiences and that of others. freshwater inverts, snails, shrimp, clams, mussels, crayfish, scuds,amphipods, etc need no more than a temp difference of 2 deg f up or down from their "bag" water and a fairly close Ph, usually not more than .3-.4 points depending on type of animal.with ph we need to remember that each tenth on the scale is ten fold. that is to say that 7.1 is ten times more alkaline than 7.0 so if you take an animal living in water that is 7.0 and move it into water that is 8.0 the Ph difference is 100 times more alkaline. so you can see where a problem could arise. With saltwater inverts acclimation is not so easy. osmotic regulation comes into play with them. salt water animals drink saltwater but they expel the salt thru their physical makeup, thus osmoregulation. salt inverts, stars & snails have the hardest time regulating osmosis, stars move and function by the use of hydraulics, the hydraulic fluid is basically osmotic regulated water. so the #1 problem for them would be specific gravity of their environmental water. If we bring a star home in a bag from where ever and the water in the bag has a SG of 1.023 (any thing below 1.024 is not adequate for inverts) and you dump it into your tank or exchange a few cups of water that has a SG of 1.025 most likely the star will die shortly due to it's internal structure having been ripped apart by the variation in pressure. with salt snails their vital organs, kidneys, etc rupture from the difference in pressure "OSMOSIS". Actually all salt inverts succumb to variations in environment when the variations are changed quickly. Ph, SG, alk, hardness. all can if rapidly altered spell death for salt inverts. an air stone or air line should never be put into a container with an invert that is going to be placed into a tank because the air drives off the dissolved co2 in the water in-turn causing a high Ph to occur, this factor is enough to kill it when placed in the tank with a greater variation in Ph value. I have learned that the drip method works very well. & can mean the difference of life or death for your animal.I will do another post on performing the drip method.

Over the years of learning the saltwater "hobby" I have made many mistakes and murdered many animals, one of the ways where I was successful in that carnage was when I acclimated invertebrates to my tanks. even now that I have learned an almost foolproof method there are still some inverts that do not survive the acclimation. I am about convinced that the problem does not lie with me but in the capture and shipping of these animals. I find it extremely hard to believe that a person dives into the ocean with a net and snags the large amount and diversity of animals that we are able to obtain. it sometimes takes me hours to catch a shrimp or other swift moving animal in my tank anyway! saltwater inverts cannot survive rapid changes in their environment ( saltwater) due to osmotic pressure . "osmosis" in reference to salt water inverts means the diffusion of fluids through membranes. as a tendency of a fluid to pass thru a membrane of living tissue into a solution where it's concentration is lower thus equalizing the conditions on either side of the membrane.This is osmoregulation, performed by the animal & the law of physics. A saltwater invert can perform this regulation but only over the course of ample time. if it's environment is altered over a short period of time the regulation procedure is disrupted and the tissues, organs, membranes rupture or the fluid balance is askew due to the fixing of that imbalance on the opposing sides. one very sound way of counteracting this insidious event is to use slow drip acclimation, doing this procedure will in many many cases spare the life of the animal. you will need test kits for Ph, & alkalinity you will need to measure the S.G, Ph & temp of the container water as well. you should have pretested your tank for these (5) items prior to starting the drip method. you would place the new animal(s) in a plastic container large enough to hold at least 1 gal of tank water. anchor a length of airline tubing in the tank place a plastic air line valve or pinch device or tie a knot in the tubing give a little suck on the tubing to get water flowing then immediately adjust the drip rate too (2) drops per second/30 drops per min.the acclimation time is governed by the variations of the container water and the tank water. if it is very far apart then it can take several hours, closer then a matter of minutes. you will know when the acclimation is complete by measuring the proximity of the tank water and the water in the container containing the inverts. when they are equal there is still one more step, the water in the drip container will have cooled down so you will then want to float it in the tank till temp is equal. if it is to large have a smaller container ready and gently pour the animals and some water into it and float it , this should not take longer than 10-15 min or less. turn off the lights when making the additions as this will reduce stress. fish greatly benefit from the drip method as well, they can regulate a bit more efficiently but I have seen them blow a swim bladder and damage their gills as well.