30G FOWLR having problems

[@knight]

My tank has looked great up till about the last week. The back side of the tank still looks fine, but on the front side starting on the glass and going to the rock, ther is a rust colored coating on the sand. it is not on the rock, and does not resemble cyano, from what I can tell.
Water paremiters all fine, except for nitrates are 20. If I stir up the top layer of sand, it disappears, but returns the next day. I can see where my worms and snails, crabs, etc, have walked through it. My first thought was diatoms, but why only on the front of the tank??? as i mentioned, the back is completely clean and clear. I dont get it.

 

[flydan]

Hey,
The location of the outbreak may have to do with lighting and water movement in a particular area. Not sure, just throwing out an idea.
Dan'l

 

[burnnspy]

I concur with FlyDan, it is a current/lighting problem and a nutrient problem.
What are the phosphates levels, do you have macro-algae and what lights do you use?
BurnNSpy

 

[@knight]

Burn,
I use JBJ 36x4 =144W PC's, and although I dont have a phosphate test kit, I use RO/DI water. I only feed every other day, unless I have people over who want to feed the fish. I have a LOT of crabs and snails. I have a penguin 400 without filters for water movement and a maxi 1200 that pumps 250 GPH. there is noticible circulation through the tank. I originally though it was a lighting issue, but why would it only happen across the front sand of the tank? that's what gets me. could it be the incandessant lighting from the room, but still yet, wouldnt I see it on the glass as well?
I'm moving my PH to sweep across the front, it will move the sand around a little, but I am weary of weather or not it will be a long term fix.
[ September 21, 2001: Message edited by: @knight ]

 

[master of all the reefs]

i had the same problem in one of my reefs right after i boosted my lighting. i added phophate remover and nitrate remover on top of small weekly water changes. i also recently added a refugium sump to that tank. no more problems to this day.

 

[joetst2]

It has all the characteristics of a diatom bloom. You can get a dragon goby and he will continuously sift the sand for you and keep it looking great!

 

[@knight]

i moved the PH and it cleared (sand stirred it up) but now its back again. darn it. it looks awful. still waiting on my salifert phosphate test kit to arrive.