On Monday,I placed a Rainford Goby (1.5 +/-)into my 90g and have not seen him since!! How long should I give it until I should concider it a loss? Other inhabitance are 2 Lyretail, 4 green chromis, 6 line wrasse, dragon goby. Tank has about 125-150 live rock so he has plenty of places to hide where I can't see.