Beginner questions from a newbie

[Ladeia3]

Hello all,

I'm starting my first saltwater tank(s). I have several freshwater tanks but this will be my first saltwater. There is so much to learn that I'm sure I've missed important information or will mess up something along the way.

Anyway, I've got a couple of questions. I'm sure they've been asked a billion times but they didn't show up when I did searches for them so decided to go ahead and ask. I am so sorry if I'm repeating stupid questions that have been asked a zillion times.

First, the tank specs:

29 gallon aqueon kit
(sunsun 304b canister filter on order, protein skimmer has not been ordered yet but will be ordered this week hopefully, powerheads have been ordered)
for now just using the filter and lights that came with the kit (will upgrade lights when I figure out what I will be keeping in there)

10lbs live rock (I plan to add more but ran out of money and have to wait for next paycheck to get more.) This was purchased from my LFS for $8.99lb.
20 lbs live sand
Tank was set up last Thursday so just starting to cycle. I have a saltwater test kit on order. Will order a reef one later on when I get closer to needing it.
Have a hydrometer already and have a refractometer on order.

Now the questions:

1) When I was setting up the tank, I had my sister helping. I provided a plate for her to use so the sand would not be disturbed. Unfortunately, she didn't pay attention and just dumped the water in the tank and ended up making the tank a cloudy mess. I thought it would clear up after a day or two but while it has gotten a lot better it is still cloudy. I did not rinse the sand first. I've seen different opinions on this. I've seen it said where you're supposed to rinse it and others say not to. Before the cloudy mess, I had not come across anyone that said to rinse live sand. Is there anything I can do to help clear this up?

2) I'm not entirely what I will end up putting in the tank. Probably something simple and hardy since I'm new. Anyway, the original plan was to setup the tank for seahorses. I'm going to use a different tank for them and will take some time to plan that tank out a little better. Anyway, I have growth on my live rock. I'm not sure what it is and wanted to see if it was desirable or not. I've seen somewhat similar pictures online. One site said desirable, live feeders, the other site said anemones that would sting any future livestock. I'm not sure how visible it will be with the cloudy water and using the camera from my phone but hopefully someone can tell what it is and whether or not I should be trying to get rid of it or thankful it is there.

Ignore the brown stuff on the sand. My kid decided to feed the fish... despite the fact there is no fish in the tank yet... nor do we ever feed that much to our other fish at one time. Anyway... that will be cleaned up shortly. Cloudiness preceded the overfeeding.

 

[Sk8r]

I fear that's grape caulerpa on the live rock, which is not desirable. It's a plant that will take over your tank. My advice would be to (wear goggles!!!!!!!!!) take a new, non-medicated toothbrush and a bottle of hydrogen peroxide, take all the rock out, and dip the toothbrush in hydrogen peroxide, scrubbing the rock brutally into every cranny, rinse, and examine again for more green. Then leave rock to sit out in the air for however long this operation takes. I would change all the water, rinse the sand, and start over. Rinse the rock in plain water, put the rock in (the treatment will not have killed the bacteria inside the rock) and this way you should have a start without the caulerpa. Any time you spot it trying to regrow, snatch that rock out and do the scrub again, then rinse it and put it back in. Treat any new rock in similar condition exactly the same.

I hate to recommend something so radical to somebody just starting, but you'll have nothing but weed if that stuff (the pic is a bit fuzzy) is what I think it is. It MIGHT be ok in a seahorse tank, but since it has some toxicity, I'm not sure of that. Certainly it will make a knotted, interlaced mesh nothing much can swim through. Nothing much eats it, esp in a small tank, and its a pita. Please wear the goggles!

I battled caulerpa in a 50 gallon for five years before I finally broke the tank down.

And please, if anyone has a different vision of what that is and what to do about it, chime in. I hate to recommend this treatment, but it's the only thing I know that kills it.

Your alternative would be to pack up the live rock, rinse the sand, change the water, and return the rock to the store and ask for a refund: tell them you're an absolute beginner and can't cope with that algae, and you would be glad to go on buying things from them but not that rock. It's just too hard to deal with without experience. You can CREATE live rock...slow, but it will work.

What puzzles me is the fuzzy pic with the algae and the bottom pic which shows clean rock. Did you leave out the bad piece, Scrub it, or is that a detail? If it's just in one place you can treat just one rock with the peroxide and be ok. If it's over everything, everything's a problem.