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William
04-23-2009, 08:22 AM
Hi,

I'm sold on using ATS. I built the simple bucket desing with 2 lights and a tank divider screen slipped into a pipe. I have to use an external overflow box as I never had my tank drilled when I started it.

So, I started 4 1/2 weeks ago. For two weeks I didn't see anything. At first I was using the blue, "Plant lights" from GE. Not very good. Also, I didn't scratch and seed the screen.

After more careful reading I realized my mistakes. I scratched up and seeded the screen with algae from my display tank. Afterwards, I swapped out the plant lights for the 23 Watt, 5100K compact fluorescents "full-spectrum" and reseeded the screen more aggressively.

Fast forward 2 1/2 weeks later. My screen is now getting algae. But its growth is very slow and only the lower half of the screen is showing any heavy growth. The top part of the screen is darkening with algae, but only in areas, and very slowly.

Any advise?

I'm trying to include some photos but haven't figured out how to attach them yet.

William
04-23-2009, 08:32 AM
here's a picture of the 1/2 covered screen. The dark half on the bottom is light-med algae growth. This is after 2 1/2 weeks with better lighting.[attachment=0:1clxlffh]IMG_0190.jpg[/attachment:1clxlffh]

William
04-23-2009, 08:38 AM
Here's my whole tank & setup. It's in the front until I get it operational, then it's going in the cabinet.
[attachment=2:2rsxzzsu]IMG_0182.jpg[/attachment:2rsxzzsu]
[attachment=0:2rsxzzsu]IMG_0184.jpg[/attachment:2rsxzzsu]

Here's the 1/2 full screen after 2 1/2 weeks. Not much. I expected to be scraping and dropping NO3&Phosphates by now.
[attachment=1:2rsxzzsu]IMG_0190.jpg[/attachment:2rsxzzsu]

worley
04-23-2009, 09:04 AM
That's really weird seeing the line across there. Did you have it the other way up before and the white area of the screen was under the water line?
It won't grow really at all under the water line, so if you can pull it more out of the water so only the bottom inch or so is in the water it will work better.
Also, how is the flow? If you fill the bucket with tank water, and put the scrubber over an empty bucket, how long does it take to fill (and what size is the other bucket)?

William
04-23-2009, 11:32 AM
The screen hasn't been turned around. This is how it's been since the start. I agree that the neat line straight across the middle is strange looking. You can't see it in the photo but there is algae forming along the screen edge that's touching the pipe. Unfortunately it doesn't seem to be creeping down quickly, at least as quickly as the bottom half formed, and in between there's thin to no algae.

The lights are pointed to this top part of the screen (I can't point them down any lower cause of the clamps). One thougth was perhaps it was a heat thing from the lamps.?. Don't know. It doesn't feel hot when I have my hands by the lights.

My overflow box is rated 300gph, but I'm sure it's not flowing this fast. I haven't timed the bucket filling, but I will tonight. The exhaust seems to be flowing quickly into the tank, though I realize that doesn't mean much to you, does it?
Could Slow Flow cause the algae to fill the bottom half but not the top, like this?

The only other thout I had was how I seeded the screen, not realizing I rubbed harder or better on the bottom compared to the top.


Any ideas?

worley
04-23-2009, 12:32 PM
Oh yes, I'm being stupid, of course.
You have the lights on 24x7 right?
Don't, 24 hour light stresses the algae, put it on a timer, have 6-8 hours off.
You will kick yourself as there is an explosion of growth =)

SantaMonica
04-23-2009, 05:21 PM
Yes, put a timer on the lights.

And, you can indeed get the reflectors down lower if you tilt the clamps sideways. After doing that, buy some smaller reflectors.

Lastly, make sure the screen is so rough that you cannot see through it.

William
04-24-2009, 07:30 AM
Thanks for all the advice.

I have the reflectors off during the day. I turn them off around 9 am and put them back on around 6 pm. Off too long?

I do need to put them on a timer though. I'll have that in place today.

As far as the screen scratched up, It's not so scratched up you can't see through it. You can see the scratches, but absolute. If the screen's not scratched up so much, will that prevent growth?
Either way I'll scratch up even more, reseed (though I'm guessing there's already a nice layer of seeding) and will start again.

Hopefully third time's the charm.

SantaMonica
04-24-2009, 08:50 AM
There is something else that's the problem. It's not the light or the seeding. How high does the water get in the bucket? Can you remove one light and get a close up shot of the flow where it hits the water?

worley
04-24-2009, 09:10 AM
Yeah, there is something else that is wrong if the lights aren't on 24x7.
You could easily keep them on another 2 hours a day, say off at 10am, on at 5pm.
What wattage are the bulbs, and how far from the screen are they at their closest?
Also, what colour temperature are they? (e.g. 3500k)
If it's a daylight (e.g. 6500k) bulb, and it's fairly new, it could be emiting too much UV and killing/stopping the algae growing. There has been reports of daylight (they give a whiter colour light) CFL bulbs that emit high amounts of UV at short ranges.
It looks similar to the problem I had when the lights were on 24x7 when I first started my scrubber, where the algae wouldn't grow near the lights.

William
04-24-2009, 09:51 AM
I'll get a shot of the flow as soon as I get home.

The bottom 4 inches or so of the screen is in the water. The remaining 10-12 inches stays above the water. The algae line is right in the middle, about 6 inches from the top. Note, I am getting algae growth on the top half, its just "very" slow. The bottom half you see came in over the last 4-5 days. The top half has about 1/10 the amount, thinly growing.

The lights: I want to say they're about 4 inches from the top of the pipe. Maybe 6. I clamped them on 6 inch tall clamps and pointed them down. The lights are 23 Watt, 5100K compact fluorescents "full-spectrum", 1 on each side of the screen.[attachment=0:31hwj9el]IMG_0191.jpg[/attachment:31hwj9el]

Could flowrate cause this kind of problem? I have a 300gph overflow box, but I'm sure it's not flowing that fast. If I had to guess I'd put it at 200 gph (I know, I know, I have to time it tonight). My screen is about 8 inches wide, so I need 280 gph. :?:

worley
04-24-2009, 09:58 AM
Ideally you want 35gal/h per inch of width, so 350gal/hour for 10" wide, but you'll find it's nowhere near that when you actually measure it.
It'd be worth measuring the rate by filling a bucket.
the 5100k bulbs are a bit too full spectrum, but they should work better than they have, I doubt it's any UV from the bulbs then. Normal cheap bulbs should be fine (around 3500k).
How fast and even is the flow?

cyberseer
04-24-2009, 06:17 PM
What I am guessing the cause of that line of algae growth might be from the pipe. Since the lights are mounted so high, can the pipe be actually acting as a light shield? I mean that is the only other thing I can imagine that would give a straight line like that. Coz that's how my screen look after I added a light shield to prevent algae growth into the slots.

William
04-25-2009, 05:09 AM
So I was right.
I timed it and my flowrate is 200 gph. I raised the pump speed and water lever a little (variable speed pump) so I now estimating around a 220-230 gph rate, but lets stick with 200gph.

Now, the top section is now semi covered with algae. There are clean patches, like some of the bottom, but it's there. The funny thing is the thickest patch of algae is along that center line we see.
The bar-shading is an interesting idea. The lights are above the bar at an angle that could be reducing the light hitting the top. I'm getting smaller, better reflectors and clamps to lower the angle, so we shall see.

The slow rate of algae growth has me baffled. This is the third week, and there's only a light covering on the screen. I expected to be scraping by now.

Let's see what happens next.

worley
04-25-2009, 09:28 AM
Is there any way you can get the flow up to 350 gal/hour?
Getting the smaller reflectors so you can get the lights closer should help. Also, you really should be doing a scraping once a week even if there's little growth, just use your hands to pull off what comes off easily.
Also, do you rinse the screen under fresh water after cleaning?... Which is a stupid question as you said you haven't cleaned it...
Clean it, rinse it, could be copepods eating the algae.

William
04-27-2009, 06:56 AM
I am getting a new overflow box with a greater speed (600 ish). With my return pump this should get me into the 300's.
And I'm getting new reflectors today, so this will help me direct the lights better.

As far as the scraping, my understand was that I should let the screen sit until I start getting green algae. Currently I only have the brown type algae. Shouldn't I wait? I wouldn't be doing a scraping now as much as a wiping off.

SantaMonica
04-27-2009, 04:43 PM
Wrong wrong wrong. Never let it set more than a week. The brown stuff must come off several times before the green will start.

William
04-28-2009, 07:16 AM
Thanks. Will be done asap.

On a positive note, the whole screen is covering up now, and the lights are lower and more focused directly onto the screen.

William
05-04-2009, 10:08 AM
So here's an update.

My flow has become pretty steady. I'm flowing at about 300 gal/hr.

My algae growth has also improved. That horizontal line is still the center of growth (very strange). I cleaned one side, and the regrowth began along that line and then spread outwards. The good thing is that growth is faster. Within a couple of days the cleaned side was full and becoming heavy again.

I've just seen green algae growth begining in a couple of spots, which is a positive thing. It's amazing how clearly the grean algae comes in.

I've also shifted my lights and added 2 more reflectors on the open sides to provide a more focused and even lighting into the bucket. This I'm sure has helped with the growth.

Now for chemicals: I'm not sure if this is wishful thinking or direct results, but my Nitrate is staying consistantly in the mid to low forties between water changes. Before starting the srcubber I had large swings, with high thirties after a change to the fifties after a week. I actually peaked at 61 about 5 weeks ago.

My Nitrates haven't gone past 45 in the last 2-3 weeks and the swings are smaller. I'm taking it as a positive note. I have 180 sqr inches of sheet (180 gals capacity) and my system is only 80 gallons, so it's possible the affects are currently noticeable.

More to come as things evolve.


And here's one more positive observation I've had. POWER OUTAGE EMERGENCY PLAN IMPROVEMENT. With the ATS and 2-3 marine batteries (approx $100 each) for the pump I can keep water flow and filtration going for up to 2 days if I have a power outage. Lighting is different issue, but the coral should be able to handle a couple of days with minimal lighting in an emergency.

SantaMonica
05-04-2009, 11:59 AM
Good to see nitrate coming under control. Sound just about right. In time will start coming down.

As for power, if you are home and the power goes out, you can just lay the screen in the water; it can sit for three days with no harm. But if you want filtering to continue, you'll need to power the pump. Algae keeps filtering (but not as much) even with the lights off.