Lots of peronsal preferences in this area. My old system had a 4 inch sandbed and I always seamed to have nitrates around 10-25ppm. So, when designing the new system I focused on a live filter system that placed emphasis on water quality and nitrate removal.
I did lots of reading and research when designing my second system. I am a premed major and have a strong chemistry background, therefore, my approach was based on chemistry, and opinions of others. I read several books and literature before deciding on the plenum system and my decision was made based on the chemical rationale behind the plenum system. The manual I found most beneficial is called "Live Sand Secrets" by Dr. Bob Goemans. ($10.00) Not only did this manual provide the chemical approach to the plenum, but it directs the reader with a step-by-step method to installing one. I followed his recipe exactly and have had nitrates of zero so far. All my other measurments have also been very good, with the exception of phosphates, but that is due to the fact that my system is only 4 weeks old and is going through the standard algal bloom.
In short, the plenum system is designed with a 1 inch anoxic zone which is designed to give a home to anerobic bacteria. These Anoerobic Heterothrophs only survive in an area without oxygen and although there contribution to converting glucose to 2 ATP (energy) molecules is small compared to aerobic respiration which contributes 38 ATP, it is still important. The other key element to this zone occurs in Anerobic Respiration, aka dentrification. Under these anerobic conditions, some respiratory bacteria substitute nitrate for oxygen in their electron transport system. Although less energy is made, the process is still highly energy efficient and specifically tagets nitrates. According to Goemans, the sand bed system placed directly on the glass does not provide an are for this group of bacteria to live and multiply. Altough they do live in the standard system, they fight for space with the sand and their contribution to denitrification is limited.
The big disadvantage I noticed with this system is that you can no longer have burrowing fish, because they will dig down to your plenum screen. I had to give up my favorite orange-spotted sleeper goby... bummer.
This is a very controverisal area and both systems have been proven effective, as for me, I have had more success, so far, with the plenum system and it was fun and easy to build. If you choose this route, make sure you read, read, read.
Cheers,
Scott
I did lots of reading and research when designing my second system. I am a premed major and have a strong chemistry background, therefore, my approach was based on chemistry, and opinions of others. I read several books and literature before deciding on the plenum system and my decision was made based on the chemical rationale behind the plenum system. The manual I found most beneficial is called "Live Sand Secrets" by Dr. Bob Goemans. ($10.00) Not only did this manual provide the chemical approach to the plenum, but it directs the reader with a step-by-step method to installing one. I followed his recipe exactly and have had nitrates of zero so far. All my other measurments have also been very good, with the exception of phosphates, but that is due to the fact that my system is only 4 weeks old and is going through the standard algal bloom.
In short, the plenum system is designed with a 1 inch anoxic zone which is designed to give a home to anerobic bacteria. These Anoerobic Heterothrophs only survive in an area without oxygen and although there contribution to converting glucose to 2 ATP (energy) molecules is small compared to aerobic respiration which contributes 38 ATP, it is still important. The other key element to this zone occurs in Anerobic Respiration, aka dentrification. Under these anerobic conditions, some respiratory bacteria substitute nitrate for oxygen in their electron transport system. Although less energy is made, the process is still highly energy efficient and specifically tagets nitrates. According to Goemans, the sand bed system placed directly on the glass does not provide an are for this group of bacteria to live and multiply. Altough they do live in the standard system, they fight for space with the sand and their contribution to denitrification is limited.
The big disadvantage I noticed with this system is that you can no longer have burrowing fish, because they will dig down to your plenum screen. I had to give up my favorite orange-spotted sleeper goby... bummer.
This is a very controverisal area and both systems have been proven effective, as for me, I have had more success, so far, with the plenum system and it was fun and easy to build. If you choose this route, make sure you read, read, read.
Cheers,
Scott
