Newish tank, is this good or bad?

[twreefer]

I have a 90g tank about six weeks old and fully cycled at 3 weeks. Started with live sand, fuge mud, quick start, and dead rock. 9 fish were added in 4 phases over last 3 weeks and doing great.

Main tank is clear, with some light brown starting on high flow areas of the rock.

First chamber of sump with sock and marine pure spheres is clear.

Third chamber of sump with just pump is clear.

Middle fuge chamber of sump with heater, mud, very small ball of chaeto, and one half- pound rock has started to turn VERY brown. Is this algae or diatom bloom? There is a patch of brown hair algae about the size of a silver dollar, hair about 1.5 in long.

It seems odd to this newbie that only middle chamber is browning, while rest looks great. Heater keeping this area too warm? (79 in tank) I suppose I should move the thermometer there to check.

 

[MondoBongo]

you're going to see some weird algae blooms on and off, usually for the first 6 - 12 months of a brand new tank.

it's probably cyano. likely it is forming there because of low flow and high light. the heaters could be contributing, but probably not as much. your tank should stay relatively homeostatic after the initial heating of the water, barring any large additions of colder or warmer water. so the temperature likely isn't spiking that much in that area.

i would just keep going with your husbandry, water changes, other forms of nutrient export, etc... assuming all systems normal, these things usually balance out and pass with time and care.

 

[twreefer]

Thanks Mondo, I wasn't too concerned, but it just seemed odd to be getting so brown in only one area. I wouldn't think low flow would be a problem in middle chamber of the sump, unless the flow pattern just bypasses the sides/bottom surfaces. I would think cyano would be a bit more red as well. Attached a pic if that helps.