Algae scrubber for natives

This post is quite overdue and I apologize to those who I have promised an account of my experiences with one. I’ve had some technical difficulties(obsolete camera/new operating system) and I also wanted to wait until it had been in operation of a while to collect as much information as possible. Ironically, an algae scrubber is actually so simple that it’s hard to say a whole lot about it.

There’s enough good information on the web about building one that there’s no reason for me to discuss the construction of it, but I can discuss how it has worked and what advantages and disadvantages I’ve found with them.
Here are some links if anyone is interested in building one: http://www.livingree...ber-t32422.html
http://www.livingree...diy-t16734.html
http://algaescrubber...orums/forum.php

I built my first one a few months ago. I’m using it on my 150 gallon tank. I then built another one just a few weeks ago for a 30 gallon tank.

I’ll start with the disadvantages:

• They’re ugly. If you choose the DIY with PVC piping and an open screen, there’s just no way around it. PVC piping and a screen full of algae is just not pleasant to look at -interesting but not pretty. You can purchase enclosed models that would be much more attractive, but that would eliminate some of the advantages that I feel they have for natives.
• They require longer lighting duration than a tank full of plants. I normally leave the lights for my planted tanks on for 10 hours a day. The algae scrubbers require 18 hours a day of lights, and fairly intense lights at that. I’ve got four 40 watt CFL’s on the scrubber for my 150 gallon and two 23 watt CFL’s on the one for the 30 gallon.
• Like any sump, you have to find a place to put it.

Some of the advantages are:

• They are very powerful nutrient removers. Before installing the algae scrubber on my 150, I was changing 20% of the water 4 to 5 times per week just to keep the nitrate level down. Once the scrubber began working up to full potential I haven’t done a water change in over 2 months and the nitrate levels are always less than 20ppm. I’m sure if I removed my canister filter, the nitrate would be 0, but I prefer to keep it running for mechanical filtration.
• They’re easy to build. The first one was a nice afternoon job. The second one probably only took an hour or so, but it was smaller.
• Easy maintenance. A quick weekly cleaning of the screen only takes a few minutes.
• They’re good for tanks where plants are not desired or the tank is too tall to get good light penetration through the water to the plants.
• They can cool the water. I love this advantage when it comes to keeping native fish as those of us keeping natives are often looking for ways to cool the water. It doesn’t cool like a chiller, but does cool. I’ve been running a fan on the screen for my 150 gallon and the water seldom gets above room temperature. When it does, it’s just for a short period. With the fan on the scrubber, the tank water temperature typically runs anywhere from 1^oF to 8^oF cooler than the room temperature. This temperature difference, of course is determined by the humidity of the room air. As with any evaporative cooling system; the lower the humidity, the better the cooling.

 algae scrubber2.jpg   189.16KB   2 downloads
This is the algae scrubber for the 150 gallon. I simply used a plastic tote and created some drain lines so it can drain back into the tank. The vertical PVC posts in the tote are just for support. The dark stuff on top is the bottom of a garbage bag that keeps it from spitting water. The bag keeps algae from growing in the slot and plugging it up which causes the spitting.



 algae scrubber3.jpg   194.39KB   2 downloads
Here it is without the lights.


 algae scrubber4.jpg   237.08KB   2 downloads
This is the one for my 30 gallon. The 30 gallon has an inch and a half drain hole that allowed me to use a 10 gallon tank underneath to put the scrubber in. I didn't need any extra support for this one.


 algae scrubber and rock bass.jpg   187.21KB   4 downloads
This one shows a little more of the set up. Please excuse the mess around it. The rock bass in the tank has to live by the recycling cans. I also like to pick up trash that I find in the creek so the rock bass gets a beat up 1949 license plate for a back drop. The PVC to the right of the picture is coming from the pump that sets in the 10 gallon and pushes the water up to the 30 gallon.

Edited by steve, 23 May 2012 - 10:19 PM.

They can cool the water. I love this advantage when it comes to keeping native fish as those of us keeping natives are often looking for ways to cool the water. It doesn't cool like a chiller, but does cool. I've been running a fan on the screen for my 150 gallon and the water seldom gets above room temperature. When it does, it's just for a short period. With the fan on the scrubber, the tank water temperature typically runs anywhere from 1 F to 8 F cooler than the room temperature. This temperature difference, of course is determined by the humidity of the room air. As with any evaporative cooling system; the lower the humidity, the better the cooling.

Wow, that's huge! An eight degree drop is really significant.

Yeah, that impressed me too. Those times have even been in the late afternoon when the tank would have normally been the warmest. It's only happened on days with very low humidity though.

Hi everyone.

I know this is an old thread, but I've been researching this a lot because algae growth and nutrient export is an obsession of mine for my build. The innovations keep on coming with this concept. Now, folks are making them simpler and smaller, and with LEDs becoming so popular, they are much less expensive on your electric bill. The latest versions are called upflow algae scrubbers (UAS), where basically the currents driving the algae growth come from below the screen that grows the algae rather than from above, enabling you to do this in a tank or in a sump, not out of the water. There are two kinds of UAS, one is a floating design, and the other is a hang on (or attach to wall) version. Both can be driven by current from your outflow to the sump, or by air stones (which are the most popular method now). Another thing that seems to be of the latest line of thinking, is that they don't have to be as big as previously thought. Some of these smaller ones grow some serious algae. Some of the fancier versions are using underwater LEDs.

I plan on constructing and using the later when my tank is up and running. I'm going to keep mine simple, a hang on using a light source outside of the sump. As far as my tank build goes, my plans began in 2007 and in 2008 came to a screeching halt for various reasons. But, I've found the resolve to complete the project as soon as I can and have critters in it before it gets too cold to collect them. I'll resurrect that thread once I have the tank plumbed, tested and water flowing.

Here are the latest discussions on these: http://algaescrubber...-Scrubber-(UAS)

For a simple DIY version, the one that I plan on doing, see this convenient video: http://www.youtube.com/watch?v=qGLnBvDkaO0

Edited by Chasmodes, 31 July 2014 - 07:35 AM.