Algae Scrubber Basics

[Floyd R Turbo]

Can I scientifically state that switching my lighting schedule is the direct cause of the growth? No. But it seems to be working.

I can, the closer proximity of the light means higher intensity. This is due to the inverse square relationship of intensity versus distance. If you halve the distance to a light source, you quadruple the intensity. This is why you have to knock back the time of light exposure. If you cut the distance in half and the time in half, you're still getting 2x the total light power delivered to the algae.

 

[redneckgearhead]

I can, the closer proximity of the light means higher intensity. This is due to the inverse square relationship of intensity versus distance. If you halve the distance to a light source, you quadruple the intensity. This is why you have to knock back the time of light exposure. If you cut the distance in half and the time in half, you're still getting 2x the total light power delivered to the algae.

That's why we like having you around!

 

[JeffBoyRD]

Great thread everyone. I haven't read it all, but I am having an issue with my ATS build. I apologize if there already is an answer but I haven't found it yet. I am building a pump fed ATS. However, upon some trial runs to the design, the flow at first thought seems excessive for the slot to handle. The water comes out at the far end of the slot. I am using an Aqueon 3000 pump to supply a 1" line. I cut my slot with a table saw and appears very straight. However, I think it is just slightly less than 1/8" wide. It is approximately 14" long at this point. I also have the PVC capped at the end of the slot run. Also the water coming out of the slot seems to continue the horizontal path it was taking in the PVC and is flowing past the end of the PVC if that makes senses. Basically it isn't flowing straight down. Thank you.

 

[JohnnyB in SD]

Although you should measure the flow, on paper that pump should be about right for a 14" screen - depending on head pressure.
Unless your slot is longer than the screen, your screen is likely too tight in the slot as you suspect. Either because you're using a thicker than "standard' screen or your slot is too narrow. Also, don't roughen the portion of screen the goes into the slot and about 1/4" below the slot. Most saw blades cut an 1/8" kerf.
If I understand correctly, "continue the horizontal path...flowing past the end of the pvc" sounds like you may have a combination of too long & tight of a slot?
The screen should fit snugly in the slot, but be able to slide into it without too much resistance. It should be necessary to use cable ties or similar to keep the screen from dropping out of the slot. If you find the fit too tight, the easiest way to alleviate the situation is to run folded sandpaper back & forth in the slot. Don't over do it though or you'll have the opposite problem, all the flow will come out the beginning of the tube and not make it to the far end.
When it is correct, water should flow over the screen in an even sheet.
Posts 2000 -10 are a good summary.

 

[JeffBoyRD]

Thanks for the reply JohnnyB. I do have a confession to make, I didn't try it with the screen inserted and mounted. If it is inserted, I can see where that will cause resistance to the flow and have some flow drop on the screen. I will try again and perhaps take some pictures of the cut as well as the performance. Also, I forgot that the supply line is 3/4" until the union just before the slotted piece. So without a picture it is 3/4", then a 90 degree, then a 3/4" to 1" coupler, the union, then the capped slotted piece.
I will take a look at those posts and check the slot and sand if necessary.
Thank you all again.

 

[Ansphire]

Also make sure your slot is 1/8".. i had a similar problem, the slot was wider tot alliwing pressure to build up in the pipe, therefore all the water came out at the end.

 

[JeffBoyRD]

Thanks for the infor Ansphire. I will try to post a pic of the slot tonight. I believe it is very straight and definitely no more than 1/8", probably 1/32 smaller. It is the width of the blade on my tablesaw.
But you did raise another question in my head mentioning pressure in the pipe. Should I consider reducing the diameter of the slotted to 3/4" or increasing the supply all the way back to the pump to 1"?

 

[JohnnyB in SD]

There is nothing wrong with using 1" slotted pipe over 3/4". I personally wouldn't even consider a smaller slotted pipe except on a mini build.
I would try it with what you have before changing the feed pipe sizes. If you're not getting adequate flow, then using 1" all the way will help reduce head pressure.
I also wouldn't mess with your screen or slot until you hook it up & see what you really have.

 

[JeffBoyRD]

Here is a pic of the PVC with the slot. I will attempt to place the screen in it and try again. Thanks everyone for the info and ideas.

 

[jimrawr]

Jeff I have the same problem with flow. My first ATS I used a drill bit to make the slot and it was terribly uneven. Then I bought a dremel, and made a second slot pipe that looked like yours, basically as straight as you can get free hand. My first slot pipe that isnt near as straight, has better flow across the screen, even though it isnt completely even. Would like to fix this issue, but when I tried to fix and made an even slot, it was worse. Any tips anyone??

 

[trueperc]

I was wondering if some one can help me and friend. I have been running an ATS for a good 8 months now. I love this thing in terms of ease of use and what it has done in the way of nitrates and phos control. Now even though I have zero on both I am not getting the thick hair type algea on my screen and I am just wondering what I am I missing. I am using the 42w compact flouresent, bulbs are about 4-6 inches away from the screen. My flow is provided by a quiet one 3000. I also have a friend that is having the same issue. I have no skimmer on this tank as well. I am just getting a type of dark green with red and slimely type algea.

 

[OkStudent]

trueperc, your ats may have used up all the nutrients over the 8 month period. Although you may be feeding the same amount it may have taken 8 months to get all your live rock cleaned up of PO4. Chances are your fish and coral could use more food, you might try that. But, if not the algae that is growing on your screen is enough to keep your nutrients low. Your conditions may be a good problem to have!

 

[srusso]

I was wondering if some one can help me and friend. I have been running an ATS for a good 8 months now. I love this thing in terms of ease of use and what it has done in the way of nitrates and phos control. Now even though I have zero on both I am not getting the thick hair type algea on my screen and I am just wondering what I am I missing. I am using the 42w compact flouresent, bulbs are about 4-6 inches away from the screen. My flow is provided by a quiet one 3000. I also have a friend that is having the same issue. I have no skimmer on this tank as well. I am just getting a type of dark green with red and slimely type algea.

The growth type is related to one thing... An imbalance in the Light to Flow to nutrients ratio.

At first glance I would say, the very first thing you need to do is, fix that slot in the tube... A stream of water shooting off the screen like that is not good, can start a fire if it comes in contact with the lights and odiously create other problems. Many ways on how to do this have been discussed in the thread.

The dark growth your showing is most likely a lack of light and flow. I wouldn't NOT feed more in this case. Fixing your flow and getting stronger lighting will help you get lush green growth we all seek.

In some cases CFL bulbs just won't cut it... Higher wattage may make hot spots, moving the light closer may do the same. T5 or LED maybe the way you have to go.

Without looking, I would guess your tank is about 60 - 90 gallons... Right?

I am finding through my own results CFLs fall short at these tank sizes and do "just enough" to keep N and P at zero, however rarely grows lush green growth. This issue is further compounded with cheaply made CFL product. This is way I am advising to not change your feeding. From the looks of it, your screen is "maxed out" and it just maintaining what it can...

Now that being said, growing the "ideal" algae isnt required to do filtering... And so long as no I'll effects are showing in your tank there is no knee jerk action that needs to happen. Plan for your next algae scrubber build to get closer to properly balancing the three. Bigger is never better here, balance is where it's at...

All that being said... This is way the new sizing guidelines have been issued. Balancing an algae scrubber is easier when one of the variables can be "set in stone". Thus the guidelines based on feeding.

 

[JohnnyB in SD]

That is similar to the best growth I could get out of CFLs too. But I didn't switch to T5s just to improve growth. I had heat, noise, and bubble issues with the CFL setup on top of my canopy so decided to upgrade the lights while building a better box.
As srusso says, it isn't necessarily a problem if your water quality is where you want it to be.

 

[zhewitt04]

I am having the same prob. Mine algae looks the same and n and p are zero but i still have algae growth in my 65. What do I need to do? The scrubber is to small to add t5's and the cost of led is expensive and I have no idea what leds i would need or want. So pretty much i need to to keep doing water changes? Just not as many? I don't understand how i hvae no nutirents but still get growth in my display?

Second thought i had was to use vodka dosing for alittle bit to clear it all up then start then hopefully the scrubber would take over. I am annoyed with my scrubber

 

[JohnnyB in SD]

You're probably going to need to provide more details regarding your ATS build or refer back to a descriptive post of it before anyone could try to effectively help you.

 

[zhewitt04]

Sorry, It is 8 months or so maybe not sure it is developed enough. I get growth about like the pictures above. I have hair algae in my tank and it grows often. I have not done a water change since Sept. I am begining to think maybe I should do one now. I have 0 nitrates and 0 phosphates. My main concerns are the algae in the display. I am tired of this problem and fed up with the HA. I use two 32 watt cfl one on each side. I have more than enough flow I use a mag 9 pump never tested the flow but on my 7 inch accross scrubber i only need like 250 gallons. I should have way more than that. Thats all the info I can think of.
Thanks

 

[redneckgearhead]

If you have the flow, then I would say lighting is where you are coming up short.

 

[srusso]

The growth type is related to one thing... An imbalance in the Light to Flow to nutrients ratio.

At first glance I would say, the very first thing you need to do is, fix that slot in the tube... A stream of water shooting off the screen like that is not good, can start a fire if it comes in contact with the lights and odiously create other problems. Many ways on how to do this have been discussed in the thread.

The dark growth your showing is most likely a lack of light and flow. I wouldn't NOT feed more in this case. Fixing your flow and getting stronger lighting will help you get lush green growth we all seek.

In some cases CFL bulbs just won't cut it... Higher wattage may make hot spots, moving the light closer may do the same. T5 or LED maybe the way you have to go.

Without looking, I would guess your tank is about 60 - 90 gallons... Right?

I am finding through my own results CFLs fall short at these tank sizes and do "just enough" to keep N and P at zero, however rarely grows lush green growth. This issue is further compounded with cheaply made CFL product. This is way I am advising to not change your feeding. From the looks of it, your screen is "maxed out" and it just maintaining what it can...

Now that being said, growing the "ideal" algae isnt required to do filtering... And so long as no I'll effects are showing in your tank there is no knee jerk action that needs to happen. Plan for your next algae scrubber build to get closer to properly balancing the three. Bigger is never better here, balance is where it's at...

All that being said... This is way the new sizing guidelines have been issued. Balancing an algae scrubber is easier when one of the variables can be "set in stone". Thus the guidelines based on feeding.

One more thing... Cleaning every 4 or 5 days may help also... Just takes longer to see the results.

 

[SPotter]

UGGH......ATS light was off for a week

UGGH......ATS light was off for a week

So we went away on vacation last friday and I returned home to find a tank full of gha and some spots of cyano. Sure enough, somehow I switched to outlet on my apex for the ats to manual off. The tank looks sooooo bad!!!! :headwallblue: