CLICK ON THE PICTURE TO READ MORE! One FREE berghia with any order of 6 large berghia. Nudibranch Berghia only consume and are natural predators of Aiptasia Anemones. They reproduce and can eradicate the Aiptasia from your tank. Aiptasia is ALL Berghia eat. Larger 1/2" bergia are better for high flow SPS tanks while smaller 1/4" bergia are fine for lower flow tanks. HOW MANY? Large infestation: 3 for 1st 10 gallons. 2 per 10 gallons thereafter. We ship Berghia which are about 1-2 months old, depending on the size as we fatten them up on aiptasia. Some thoughts when you add Berghia to your tank. - Berghia last for quite a while in tanks to about 5-8 months. - Release with powerheads off by rockwork and switch off lights to minimize fish thinking you are putting in food. Do not release directly on Aiptasia. Place them nearby. They will find the Aiptasia. - While you can sometimes see Berghia during the lights on cycle, they are nocturnal predators. - Keeping a separate tank for your Berghia requires maintaining it like your display tank. Temperature about 78F. Air bubbler without the stone (low bubble count). Water quality like display. Keep tank clean. - If you have another aiptasia predator, they might be a predator to a Berghia, including peppermint shrimp and fish like butterfly fish. Not recommended. A note on the beautiful copperband butterfly fish. They are very difficult to keep alive when put into tanks. Please serioiusly read up on these fish before you put them in your tank. You will notice that copperbands pick at many things, including corals, clams, inverts and will most likely erradicate your tank of featherdusters and worms. - Nocturnal carnivores like arrow crabs, sally lightfoot crabs, larger wrasses (corris, etc) also eat may eat Berghia, especially in smaller tanks. The fish really don't eat the Berghia since they taste like aiptasia, but by taking tasting bites they can injure the Berghia. Contact us if you have any questions.