Brown stuff on rocks (not on sand)

[marlinnhag]

hello... Tank has been up and running for about 2 months.

Its a 75 gallon. FOWLR. Dont know the exact pounds of live rock. But quite a bit. Put live sand in when I started too.

Just running a Protein Skimmer, rated for a 150 gallon tank and use a mechanical filter for random cleanups. (not 24/7)e Cyno?

I feed about once every 2 days. My only tank inhabitants are 2 three strip damsels and one fiji blue devil. (cycle was finished before adding them)

My lighting schedule is funky, dont have it set on a timer yet. Id say lights are on 3-5hrs a day (closer to 5) The lights are LED.

Ok. Brown schtuff has started growing on my rock. Maybe Diatoms? Maybe Cyno?

I took one piece of dead coral out (been dead since the early 60s) and rinsed it under hot water for a minute or two. The brown was gone, though there is a little green that just showed up.... Anyways here is a clean piece vs. a dirty piece. Any ideas on what this brown stuff is?

(dirty on right, clean on left)

Sand is bright white.

Thanks!

 

[Bobborocco]

most likely cyno. turn the lights off on the tank for a couple days. you can also take a blanket or something and cover the tank completely for 2 or 3 days. That should clear it up for you.

 

[mikecc67548]

Leave it go for awhile and export as much as you can. let it cycle on thru. otherwise you just be constantly fighting it. All kinds of things need to balance in a tank besides beneficial bacteria. It takes awhile. I assume you got other tanks with a join date of 10 years ago.

 

[namxas]

Looks like the expected diatom bloom to me. DON'T remove it, or fool with it...that will only make the bloom take longer to burn itself out (generally lasts a 2-3 weeks). You can clean the viewing panes, but leave the rest alone.

FWIW, this is something I learned the "hard way" decades ago when I was a SW noob...someone I knew to be very sharp finally told me to leave it alone. Before then, I kept removing it and it kept returning...I was going NUTS.

 

[rchrdpnc]

I have a white frosty glaze subtance growing on my live rock any suggestions?

 

[marlinnhag]

I guess I'll let it be for a few weeks and see what happens. Its just so freakin ugly!

 

[namxas]

It will get way worse...just hang in there.

 

[G4546]

Looks like the expected diatom bloom to me. DON'T remove it, or fool with it...that will only make the bloom take longer to burn itself out (generally lasts a 2-3 weeks). You can clean the viewing panes, but leave the rest alone.

FWIW, this is something I learned the "hard way" decades ago when I was a SW noob...someone I knew to be very sharp finally told me to leave it alone. Before then, I kept removing it and it kept returning...I was going NUTS.

It will get way worse...just hang in there.

My advice is to listen to this advice above. This is proper information from someone who is looking out for your better interest.