# Tired of green dust - UV time???



## Bert H (Mar 2, 2004)

First of all, it appears to be green dust - gets on the glass, kinda slimy, doesn't seem to affect anything else. It's on my 50 which was set up in December. I thought I was winning the war because it used to be two days before it came back and I have managed to push it to 4 days, but frankly, am tired of having a slimy glass every week at water change. I expect a little, but this is too much. So... am thinking of going the UV route.

Questions:

Anyone out there gone this way before, ie, UV? Did it work well for you? If so, how long to you leave it on for? Any effects on the other ferts in solution, like iron and micros? I was looking at this as a possibility - 9W size. Comments?

I have tried scraping, wiping, vaccuming as much as possible. But I need a second set of arms to vaccum as I scrape this stuff off. 

TIA.


----------



## Scoutmaster Steve (Jan 12, 2006)

I run a UV on my 125. I did so mainly to combat ich with my Clown Loaches and my upside down cats. A side effect of this is I see no algae in this tank and my ferilizing schedule leaves much to be desired. I think my UV is a 15 watt, don't remember for sure now.


----------



## Simpte 27 (Jul 16, 2004)

UV worked like a charm on my 75. 2 full days the water was sparkling.


----------



## BryceM (Nov 6, 2005)

Bert, are you dosing EI? Do you check nitrates? I was using EI without checking any nitrate levels and had a horrible infestation of green dust. When I got my Lamotte kit the NO3 was >80 ppm. It seems I was overdosing the NO3 quite a bit. I got it down below 30 and the problem disapeared almost overnight. I'll freely admit that it might have been somethings else, but that's what worked for me.


----------



## Bert H (Mar 2, 2004)

> Bert, are you dosing EI?


 Yes, a modified version of it.



> Do you check nitrates?


 On this tank, I have been checking NO3 and PO4 for the past two weeks. The levels are fine. NO3 has ranged betwen 8-20ppm, the PO4 between 2-3.5ppm. I use a Hach kit for the nitrate, have used LaMotte and another cheapie for PO4.

It's lit by 2 - 55W ahs retrofits, one bulb is 9325K, the other is 6700K, 10 hour photoperiod. Tank is an Oceanic.


----------



## MatPat (Mar 22, 2004)

How sure are you of your CO2 levels? Green Dust seems to appear in my tanks mainly when the CO2 level drops.


----------



## Bert H (Mar 2, 2004)

> How sure are you of your CO2 levels?


 They're up there. Tank pH is 6.8, atmospheric equilibrated tank water is 8.0. kh is 9.5.


----------



## jrIL (Apr 23, 2005)

Tom Barr suggested a method to rid of GDA that he hs been experimenting with. His working idea is that GDA needs to cycle away by exhausting itself. Here is what he had us try.
Let the GDA alga go wild for up to two weeks. Fight the urge to clean the glass. As the dust uses whatever it feeds on it will start to die off and start to get gray in color. At this point kill the light for a day, then 50%water change. It worked for me. Took a little over a week. GDA has not returned for 10 days now. 
He is not saying this is a cure yet but it seems to work for several folks.

JR


----------



## Avalon (Mar 7, 2005)

I had a major problem with GDA. I was using the EI method. I went for the UV method, but it did not cure it, but it did slow it down--by about 1 day. Here's what I did:

I re-checked my water co.'s report, and figured what a heavily planted tank with good CO2 would use (nutrients). I figured about 4ppm NO3 & 1.0 ppm of PO4 per day to start with. After figuring I'm not getting an actual 75g (for a 75g tank) of water using the fertilator, the .5 tsp & .125 tsp measurements would work, respectively. After going with this, I re-checked my CO2 to make sure I'm getting proper circulation of mist. I later found that proper circulation of CO2 is the key. But these nutrient levels have worked very well, although I've adjusted the PO4 to a tad bit more, but less than .25 tsp.

My conclusions are that CO2 and really, really good circulation were the key that allows the plants to suck up the nutrients like they should. Once circulation dropped, either due to filter outflow slowing (using a cannister to disperse CO2, and a powerhead to circulate) or the plants blocked the water circulation, algae began taking a foothold. The steps I took to correct this issue were to keep the powerhead /w quick filter attachment very clean, prune the tank more often, and rid the cannister of it's CO2 dispensing duties in favor of a better dissolution design--the powerhead/custom spraybar method. The nutrient issue boggled me for a while, but I realized that towards the end of the week, about day 4/5, nutrients were building up, and was the reason I modified the "recommended dosage" in favor of a minimalist approach in order to grow from that. I also modified my dosing regimine so that I actually skip the 3rd dosing of macros, then do a water change on the seventh day, so it's like this-->Ma-Mi-Ma-Mi-skip-Mi-WC then Ma. What I noticed was that I got GSA (not GDA) by about the 6th day. That meant either my CO2 was not in order, or my PO4 wasn't. This is the reason I adjusted my PO4, as mentioned in the last line of paragraph 2. Works great now, and no more GDA. I'm thinking that if things aren't 110% from the get go, GDA is a PITA to get rid of when nutrients are aplenty.

The one thing I have learned for sure, is that UV sterilizers DO NOT affect micros one bit when dosing regularly (daily or semi-daily). It's just another wives tale IMHO. I run an 18w Coralife UV 24/7 on my 75g, and plants are whoopin' butt.


----------

