My fish room filtration and water change system is something I found online and modified to suit my needs.  This is what you will need (roughly – it’s open to adjustment of course)

1 - 270 gallon IBC tote with top cut off

1 - 50 gallon plastic drum

6-7 - bags lava rock

1 - 3-5 gallon bucket

1 - sheet filter floss (cotton texture)

1 - large sheet filter floss (fine)

1 – fountain/pond pump

1 - ¾ inch vinyl tubing (length varies)

1 - hose clamp

1 - drill and drill bit (size up to you)

1 - large heater

1 - air pump with miltiple outputs

2 - 5ft lengths air line

2 - large air stones

First thing I did was obtain my tote.  I got two from craigslist for around $140.  He even cut the tops off for me.  I then grabbed a $20 fifty gallon plastic drum from the farm store in town.  Stopped by the local hardware store and bought seven bags of red lava rock.

The most time-consuming step of the entire process begins with the lava rock.  You must now rinse the red and dust out of the lava rock.  This process took me about two days to complete.  Granted I did not spend the entire twenty-four hours rinsing.  But it is a process nonetheless.  I found the easiest method to be placing a screen between some two by fours and setting the rock on the screen.  Use the hose to run over the rock repeatedly until nothing but clear, pure water runs off.

Now go ahead and grab the plastic drum and your drill.  Drill holes along the side of the drum towards the bottom.  I am no perfectionist so my holes are sporadic.  I guesstimated the height of the lava rock in the drum and once again drilled around the drum.  I put a few holes here and there simply because the space looked wasted between the top row of holes and the bottom row.  Now rinse out the drum.  Make sure to get rid of all the little blue pieces of plastic.  I used a razor blade to clear out some that were causing trouble.

Place the drum with holes into the tote and add the CLEANED lava rock to the drum.  At this point I added water up to the top layer of holes.  This tote will by no means be filled with water.  Mine currently remains around a third full.  An addition was just made to the filter per the suggestion of fellow livebearer enthusiast Charles Clapsaddle; pothos (house ivy) has been added to the drum.  It's roots will grow into the lava rock and help absorb the waste materials coming from the tanks during water changes.

Grab a cheap bucket and your drill.  Drill holes into the bottom of the bucket.  Take the fine filter floss and place it into the bottom of the bucket.  Use as much as you feel necessary.  Grab the cottony filter floss and put a hefty chunk of that on top.  Now place this bucket on top of the lava rock.  I have my bucket suspended above the rock with a stick.  I really doubt it matters but I like the noise it makes as it cascades through the bucket onto the lava rock.  This bucket with floss is what I found I needed to keep all the debris from the tanks out of the main water supply.  I clean the floss from the bucket about once a week and add more depending on how gross it is.  You can add a carbon floss as well to keep up quality and avoid a smell (mine hasn’t seemed to smell).

Next we need to add the airline tubing to the air pump and get the air stones in for water circulation and oxygenation.  Now get the fountain pump and hosing.  Use the hose clamp to attach the hosing to the output of the fountain pump.  I have a syphon head at the end of my hose.  This lets the hose float when I’m adding water to tanks.  Keeps the water from disrupting plants, sand, gravel, etc.

Place the fountain pump with hose attached into the tote and the hose end into the bucket with the filter floss.  Plug ‘er in and you are ready to go.  Add the heater to the tote to keep the water temp ready for changes and you are set.  I have a cycle during the week for changing water in my tanks.  This way I can adjust the heater in the tote before I change the water in the different ‘ecosystems’ I have established.  Warm the water up for S. American and let it cool down for native goodeids and colder water species.

The idea behind the filter and changer is that as I pump water out of the tanks it will flow into the filter floss and catch any debris.  From the bucket it will drain into the lava rock which will have plenty of beneficial bacteria built up.  The fountain pump will pull the water from the drum into the tote and run it back into the bucket of floss as the cycle repeats.  I have had this up and running since March 2013 and I believe it makes everything so much easier.

About every 6 weeks I drain half of the tote into the garden and add fresh water.  When not changing the water I leave the pump on and the end in the floss bucket.  This continuously recirculates the water from the tote to the floss and through the lava rock.

Let me say one final word before I end.  My eventual goal (funding dependent) is to get all my tanks drilled and create an overflow using this filter.  I will upgrade my fountain pump to a waterfall pump and let the rest run its course.  I am a bit hesitant of this because of the differing water temperatures but it sure would save a lot of time and be better for the fish as it would change out the water numerous times daily.