Growing green and brown stuff

[JammyBirch]

I started a 25 gallon tank in the late spring with sump. Got it set up with a skimmer, dry rock, live sand. Then summer hit and I stopped the build, I have water in it, circ pump and an led light. I thought it would be safe to just leave it circulate and do top offs, turns out it's growing stuff.

I don't see how, there was nothing in it. So the big question is what to do now.

My plan is to get rid of the rubble and sand in the sump, replace it with new, do a 50% water change. Since the rock is dead I'm getting a seed rock to start an official cycle, and test the water for a few weeks.

Anything else or different that you'd recommend? I have no idea what the water quality is or what is growing in there.

 

[nmotz]

Well, to me your tank sounds cycled already and I'll tell you why. That "green and brown stuff" is algae and it feasts off nitrates, which means you've already zeroed out your ammonia and nitrites. Abundant nitrates in the tank means the tank is cycled. Dry rock becomes live after an extended period of time so there's no need to buy more live rock because what you have is already covered in beneficial bacteria.

Also, if you get rid of the sand and rubble in your tank it will remove a lot of the beneficial bacteria so you might have an ammonia spike or "mini-cycle" take place when you do that. If you do, then just wait until you see no more ammonia or nitrites and test for nitrates to make sure that the tank is stable before adding anything to it.

Now, to get rid of the bad algae you should get some chaeto (macroalgae) for the sump. That will begin to absorb some of the nitrates in your system. Run lights on it, preferably at night for at least 12-14 hours per day. To deal with the bad green and brown stuff in the display tank you can just do a total blackout until its gone. Then you should probably do some water changes to reduce those nitrates even further. Good luck!

 

[JammyBirch]

Go it all cleaned up I opted to do so just because I had no idea what was going on and I picked up a few small live rocks to start a new cycle. I got the rocks because they were very clean and had amazing growth on them. In the middle of a 15% water change. I think you were right about a mini cycle...the nitrates were significant everything else was zero.

Anyway it cant hurt ...I dont have any fish in there yet.

 

[nmotz]

Just test for nitrates and then take care of those with water changes, a protein skimmer, and chaetoalgae and you should be good to go.

 

[JammyBirch]

Little update...noticed I have 2 tiny white starfish that came with the live rock...pretty cool. Did some research and they are not great, the eat coralline algae which I'm trying the grow. The other thing I noticed was this very small tube thing, the only reason I noticed it was when the light went to actinic light it had some long skinny white tentacle looking things that came out they were pretty long. Any idea what this could be? I can't get a pic I tried but it's tucked between rocks pretty tight.

Other than that everything is ok i guess really want to see some algae grow on my dry rock...can't wait.