Newbie here with Questions and Concerns

[BlooPoetato]

Hello Everyone!

I just started cycling a 5.5G and I am super excited,
I don't know what my salinity levels are but I used 3 gallons of marine water that I bought my lfs and topped off with ro water
I am using crushed coral as my choice of substrate and the tank currently has a sponge filter to help with cycling and seeding; not sure if it's a good idea or even helps but it's from a FW tank. I most likely will take it out before I introduce the OUs and replace it with an air stone for aeration.
Ordered some macroalgae, which have not yet arrived
Not sure how I feel about the shrimp shelter(had them lying around) might remove them later, still playing with the scape
The room temp fluctuates between 68-72 and the 50's at night during this time of year, i'm thinking about putting a heater in and setting the temp to about 74-76
Another concern is that I'm not completely sure what the yellow'ish white rock is or if it's OUS safe
The LFS employee said he's pretty sure it's just an ocean rock which I assume would be safe(?) but I have my concerns.
I'm just hoping it's not some sort of dry live rock that becomes alive once it's in water or something... lol...
I want to buy and scatter 2 inch lava rocks to create more surface area and hiding spots for the shrimp,
but it seems the most readily available lava rocks in that size are generally used for fire pits
I read somewhere that that's okay? but I guess I just really want a second opinion and some reassurance.

Thank you everyone in advance
and Big Shout out to Mustafa! Lots of valuable information!

[sliphorn]

Hello Everyone!

I just started cycling a 5.5G and I am super excited,
I don't know what my salinity levels are but I used 3 gallons of marine water that I bought my lfs and topped off with ro water
I am using crushed coral as my choice of substrate and the tank currently has a sponge filter to help with cycling and seeding; not sure if it's a good idea or even helps but it's from a FW tank. I most likely will take it out before I introduce the OUs and replace it with an air stone for aeration.
Ordered some macroalgae, which have not yet arrived
Not sure how I feel about the shrimp shelter(had them lying around) might remove them later, still playing with the scape
The room temp fluctuates between 68-72 and the 50's at night during this time of year, i'm thinking about putting a heater in and setting the temp to about 74-76
Another concern is that I'm not completely sure what the yellow'ish white rock is or if it's OUS safe
The LFS employee said he's pretty sure it's just an ocean rock which I assume would be safe(?) but I have my concerns.
I'm just hoping it's not some sort of dry live rock that becomes alive once it's in water or something... lol...
I want to buy and scatter 2 inch lava rocks to create more surface area and hiding spots for the shrimp,
but it seems the most readily available lava rocks in that size are generally used for fire pits
I read somewhere that that's okay? but I guess I just really want a second opinion and some reassurance.

Thank you everyone in advance
and Big Shout out to Mustafa! Lots of valuable information!

..
Was the freshwater top off done after the gravel and ornaments were put in? Those things displace water, but either way you are above 50% seawater. Not the end of the world and the opae ula will do fine. Buy an inexpensive hydrometer at the pet shop if you have the urge to check the levels.

The shelters have a lot of surface area to grow bio film on, so that's good. But only you can decide if you like the look of them.
You do not need a sponge filter either, it really is not needed.

Go to a home improvement center and buy lava rock in the garden department, the type that is used for landscaping. It works great.

The macroalgae will definitely help! Good luck.
..

[Super Jess]

That white rock is super cool.

[Dch48]

The heater might be needed but 72 degrees would do fine.

[Dch48]

That white rock is super cool.

It looks like lava rock but I've never seen it be white.

[Super Jess]

It looks like lava rock but I've never seen it be white.

Looks like limestone!

[Vorteil]

I think you're good where you're at except the salinity. I think it's going to be on the high side. That I would check and not assume it's good. 72 degrees is in my opinion an ideal temp. That's where I try to keep my tanks at year round. Remove the sponge filter once it's cycled.

[Mustafa]

So, did you follow the advice given here? How's your tank going?