New Reefer Needs Help With Blue Haliclona sp. Sponge

[Emanuel refer]

Five days ago I was at my lfs and saw a blue sponge. I wanted a blue sponge for a long time so I decided to buy it, i knew that it was a Haliclona sp. sponge because i did some research before buying it. It was sold me under the name of "Blue Sponge" , i know that it shouldn't be out of the water so I decided to pick him up by myself, the employees from the store didn't had any problem with that, and gave me a bag that I filled with water inside of the aquarium and put the sponge in the in the bag so that it didn't touch the air. When i arived home i drip acclimated the sponge and then put it in the tank (without touching the air) . The next day i saw some brown spots on the sponge but the spots didn't grow and also the oscula opened . In the third day i saw some new tissue growing on the oscula but it didn't close the oscula it just rearrange it . Also the sponge has two oscula openings one big and one small the new tissue growth was on the biggest one. I feed the tank daily Tropic Marin Reef Snow , Aquaforest Pro Bio S i am also waiting to arrive some live phytoplankton and Aquaforest Pro Bio F. On the rock with the sponge is a encrusting SPS coral i think that the coral won't survive but my main focus now is the sponge. The tank has 45 liters about 12 gallons it was started with live rock from 6 diffrent sources , in a corner of the tank i have a big ball of chaetomorpha that is growing. No fish, snails from the live rock , 1 clibanarius hermit crab , Green Star Polyp coral, Gorgonia coral , Xenia , Kenya tree , a red mushroom coral and the sponge . I like a naturalistic approach to reefing so i don't have a skimmer . Some levels of some tests are : NO3 = 0.50ppm PO4 = 0.01ppm Calcium = 480ppm dKH = 7 PH = 8.5 . I am new to reefing this is my first tank it has about 8 months . So if someone can help with some info about the sponge care or some tips please consider sharing . Here are some pics of the sponge and the aquarium : 

[mitten_reef]

looks pretty healthy to me.....not sure what specific concerns you have, if there was any.  and that's a really nice color sponge!

 

as far as keeping sponge, there are a couple of sponge supplement on the market I'm aware of: KZ SpongePower, Brightwell SpongExcel.  There may be others.