not getting the results i want

[deepee]

HI everyone , just looking for a bit of advice ,
i have had my scrubber up and running for about three months it is filtering a 40g mixed reef tank
the specs on the scrubber are
a 6" by 8" double screen/double sided
the water is fed to it by a 1000 lph pump and the over flow from the tank which i estimate to be probably about 700 lph by the time
it gets to the scrubber .
lights are two 35w cfl at 2700k which is the highest watt and the lowest temp i can find in this part of the world .
on the 18 hr cycle.
the problem is that i haven't been able to eliminate the gha in the display with scubber alone and i cant seem to get consistant green growth on the screen
it always starts brown and then when i do get green coverage it comes off really easily even with the lightest cleaning and i have to start from square one .
i have attached some pics .
hope you get the idea .
what am i doing wrong ?
cheers dan

[attachment=0:vvivk8wd]DSCN2083.JPG[/attachment:vvivk8wd]

[attachment=1:vvivk8wd]DSCN2084.JPG[/attachment:vvivk8wd]

[SantaMonica]

Move the lights further down, and closer to the screen. Higher nutrients just need more light to get green.

Clean out the bottom of the bucket, but don't let it flow into the tank.

Can you lift up the pipe and show the flow off the bottom of the screen?

[deepee]

unfortunately i cant move the pipe as it is fixed , but the flow is all the way across and a solid wall ish .
maybe i just need more flow than i have ?
i made the changes you sugggested.
so ill see how it goes .

[SantaMonica]

Those are strong lights... things should be better within 4 weeks.

[deepee]

thanks for the immediate reply its much appreciated :)

[deepee]

just a quick ask , would it be possible for people with very succesful scrubber screens to take picks of the algae on them so that we can get a bench mark.
is brown or is green?
have other people had luck getting green with 6500k bulbs?
cheers

[deepee]

well im so close to chucking this scrubber idea out , but i see so many other benefits to the system im reluctant to.
i am loosing the battle with the gha in my dt rapidly .
i just never seem to be able to get good green all over .
in fact the more algae i get on the screen the more it appears in the dt .
HELP!!
i made some more changes a month ago 2700 lph flow on screen extra 23w each side .
just dont seem to get fast growth on the screen .

[SantaMonica]

How much are you feeding each day?

What are N and P?

I need more pics of the screen at 7 days. The one pic I saw looks like there is a bald spot from too little flow. Double layer screens need more flow, at least 40 gph per inch, which is 152 liters per inch. Your 6 inch screen would need 900 lph. So lets see more pics at 7 days. If it is a bald spot, and if you cannot increase flow, then you can either switch to a single layer screen with a smaller slot, or move the bulbs further back, or run the bulbs less hours per day, or switch or smaller bulbs.

You can also add some iron, like Kent's Iron+Manganese (per instructions on bottle), which helps the algae from burning.

You probably have lots of places in your tank and/or sump where food is settling and rotting. My guess is you have sand too. So you are needing higher scrubbing power to get the nutrients down. And if you are burning the algae, then it can't filter strong enough.

[sklywag]

To let you know. Algae on my scrubber tends to be green with a brown tint.
Flow may be too much on scrubber washing it off sending it back to display. Check roughness of screen or slow flow a little.
Manually pull GHA from display to help. Rocks may be saturated with Phosphates and it's leaching out as the scrubber works so you're seeing it being drawn out. Thus the idea as the scrubber grows so does the display.
I'm using cheapy 23 watt bulbs that I don't even know the lumens or Kelvin on.
Stick with it.

[sklywag]

I guess it's more brown with a green tint.
http://i874.photobucket.com/albums/ab30 ... ber007.jpg (http://i874.photobucket.com/albums/ab308/ddinox64/scrubber007.jpg)

[SantaMonica]

Add some Iron

[sklywag]

Could that be in the form of nails? Thought I read that somewhere.

[deepee]

well i feed once 3 days a week
the last tests i did was nitrate near zero and phosphate well under .2
wont the iron encourage the algae in the dt
and i think that 2000 lph is quite enough then for a double screen .
should i be cleaning more often if i'm getting more of the brown stuff.

[SantaMonica]

Has to be Kent's Iron+Manganese, not a nail. If iron is the weak link in your scrubber, then more iron will allow it to grow.

[deepee]

can it be this Seachem Flourish Iron 100ml .

[SantaMonica]

Any brand, but no nails

[deepee]

and what would the dosing strategy be?
im also worried its going to make the algae in the dt stronger too.
am i not going to make my issue worse .

[SantaMonica]

Folllow the instruction on the bottle, and add more each day until the yellowish growth turns green. It should not do anything to the display.

[piratefish]

Stick with it ! My tank looked like you could use a weedeater in it. After almost a month I have brownish dark green growth. Not very thick but there is no HA in the DT.

[deepee]

how much flow do people have coming from there tank into the scrubber?

the scrubber screen has its own 2000lph pump from the water in the bucket , but the water in the bucket is from an over flow from the tank which is
cotrolled essentialy by the return pump , which is 2000lph but has to push the water up 1.3m back to the tank . do i need a more powerful return pump?
to process more tank water?

[SantaMonica]

How does the water get out of the bucket?

[deepee]

the water in the bucket has a return pump , which is 2000lph but has to push the water up 1.3m back to the tank . do i need a more powerful return pump?

[SantaMonica]

The over flow from the tank should just go to the scrubber pipe. Then a single return pump should send it back to the tank.

Only one pump needed.