Interview with Mr. Leng Sy on Mud Filtration
Copyright Albert J. Thiel, 1997
On Dec. 3, 1997 I
called Mr. Leng Sy, the owner of Ecosystem
Aquariums after a few email
exchanges with him requesting a telephone interview to
obtain more information on the filtration, 
its components
and more details on how the aquariums are maintainted,
what type of additives are used, and so on.
My sincere thanks to Mr. Leng Sy for taking the time to talk to me, and give me a lot of information that has not been published before. Mr. Leng Sy was extremely kind and put up with my many questions giving me answers and suggestions and explanations needed for all of us to understand this new form of filtration better.
If you have been to the Ecosystem Aquarium Web site you know that the tanks look superb. The system is obviously giving superior results. Just check the graphics showing tanks and corals and you will be convinced. If you have not been there yet, I suggest you use the link provided to do so. Here it is again: Ecosystem Aquariums
The aquarium itself is set up as a Berlin System with the normal amounts of live rock you would use. I suggest 3/4 to 1 lb per gallon maximum. There is no substrate in the tank itself. The bottom is left bare as it will soon be overgrown by calcareous algae and other organisms anyway.
For a while you will see the glass or acrylic but after a short while that will not be the case. Of course you could place small rock so a minimum of the bottom is exposed. Mr. Leng Sy did not seem too concerned about not having any substrate in the tank. The live rock is what is needed and, of course, the Mud in the sump.
Mr. Leng Sy calls it MUD though. Note that when you order this MUD from Ecosystem Aquariums, it will be shipped to you in dry form. You add it to a compartment or area of the sump and then add water, let it settle and then start the pumps.
What struck me right from the start is that when I asked Mr. Leng Sy how much circulation was needed through these system, his answer was a lot. In fact in a 120 gallon system that he has set up, he flows about 1000 gallons per hour through the sump.
The sump is the area where the apparantly very beneficial filtration occurs. Judging from the results that can be seen on the web site, the filtration is working extremely well indeed, especially since NO skimmer is used. You read that correctly: no skimmer is necessary on this system.
Gee, and here we talk about bigger and bigger skimmers all the time, and suddenly we see a near perfect system that does not use any at all. In fact, Mr. Leng Sy is against using them as they deplete the beneficial nutrients from the system.
Sounds familiar? Overskimming? Seems like Dana Riddle and I may have been suggesting an approach without a solution and that Mr. Leng Sy has provided a means to do away with skimmers altogether.
Do you see any ill effects of not having a skimmer? On the contrary according to Mr. Leng Sy. Without a skimmer his system doesn much better, not to speak of the reduced amount of work needed to maintain skimmers and the cost savings achieved by not having to buy one.
Are they negative effects of not using a skimmer: not that I can see if you look at the results he obtains. Check the photographs on Ecosystem Aquariums when you have finished reading the article. It is worth you while.
I asked Mr. Leng Sy what he attributed the success rate of this type of filtration to. He suggests that it is a combination between the Mud, the Algae in the sump (see later) and the live rock in the tank and not using a skimmer so that beneficial elements are not removed.
I was quite surprised by the answer I received to the question: how much MUD was needed. Apparantly all the 120 gallon tank uses is an area 24 inches long by 12 inches wide by 1 inch thick, in the sump, or about 30 pounds of MUD. That is substantially lower than the amount of live sand one would use in such a tank.
The composition of the MUD cannot be revealed unfortunately as that is considered commercial property since Ecosystem Aquariums sells the MUD ($8.00 per pound). Mike Paletta in his article that can be accessed via our site or on the Ecosystem Aquariums site, desscribes the make up of the MUD somewhat. Note that Mr. Leng Sy indicated that it is brownish/black in color.
An important point to note is that, yes, the price may be considered high compared to live sand but since you need a lot less of the mud to have a successful system you will be saving money anyway. A 30 gallon system would probably only need about 6 or 7 pounds and a 55 not much more.
The Mud is placed in the sump and leveled out to be about one inch in thickness. The area it takes up becomes larger as the size of the tank increases. In the 120 gallon system he runs it is 12 x 24 x 1 inch. Although the tank is only 120, Mr. Leng Sy feels that he could easily run a 180 with the same quantity of MUD and Algae.
Note that the algae is Caulerpa sertularioides and not C. prolifera as may have been indicated elsewhere. Mr. Leng Sy indicated that he has experimented with several types of Caulerpa and that C. sertularioides appears to give the best results, and is more resistant and does not die off. Very little is actually placed in the tank when it is first set up. A few strands is all that is needed. They grown quickly. And, yes they are "planted" in the MUD. It is also relatively easy to obtain.
When asked about additives the following were the suggestions:
- In SPS tanks: add KW and buffer when needed
- In soft coral tanks do not add anything
- In SPS corals, add very little or no KW
Water chemistry is maintained by water changes (about a total of 10 percent per month). Smaller amounts can be changed weekly is one prefers that schedule.
When water is removed from the tank it is taken from the bottom together with whatever detritus may have accumulated there. This ensure that pollution is taken out.
Within the sump an area for light mechanical filtration exists, using bioballs, to break up larger detritus (this is described by Mike Paletta in more detail).
Well so much for Part I meant to give you a general overiew. Part II will follow either later today or tomorrow with more details yet.
The first part of this documented has resulted in a large number of private emails wanting more information about certain aspects of the system. Some of this I already had, some of it I had to Email Mr. Leng Sy to obtain the answers. He was kind enough to respond quickly as I had the answers to all the questions within hours. I am sure more questions will come up. If they do I will email him again and hopefully we will get some more input from the originator of this new filtration system.
Basically the Ecosystem ™ goes against the grain of a lot of what we are doing right now, yet seems to give excellent results nevertheless. No skimmer is used, no live sand is used, and Mr. Leng Sy is not even convinced that live rock is necessary. Rock is though, as long as it is porous, it will pick up a sufficient biological filter during the cycle. The MUD does the rest in combination with the algae that grow in the system.
In Mr. Leng Sy's own words: in tanks run by the Ecosystem Filtration live rock is used more as a decoration. It makes the tank look more natural. It is not that important for the filtration, as the filtration really occurs as a result of the Mud and the Algae, and the prefilter filled with bioballs for mechanical filtration.
Remember the real strong current too. This is conducive to bringing nutrients for removal by the mud (sometimes refered to as Magic Mud) and the algae on a continuous basis and rapidly to boot.
Although other forms of algae may work, Mr. Leng Sy points out that his testing has demonstrated that the one best suited is indeed C. sertularioides. It is hardy, easy to obtain, grows fast, and does a good job at polishing the water in combination with the Mud. Without the Mud you would not obtain the same kind of results.
Whereas most of you reading this may be more interested in the application of the Mud filtration system to reef aquariums, it can be used with excellent results in fish-only aquariums (Check the Ecosystem Aquariums, web site, particularly the article on HHLE).
Parameters in such tanks are stable, nitrates are low and the pH remains at acceptable levels (8.2 to 8.4). Mr. Leng Sy indicated that with water changes and proper detritus removal, nitrates remain around zero parts per million.
Another question that came up was the type of salt use. Well interestingly enough it kind of matches up with the results of the survey we recently conducted on salt uses in reefs, as the system is ran with Instant Ocean Salt. Many types of salt have been tried and it was found that Instant Ocean gave the best results.
During the MACNA X convention 2 tanks will be set up using artificial rock donated by Aquarium Systems, supplemented by a small amount of live rock. For those going to the convention that should definitely be an interesting exhibit to go to. To find out details about MACNA X, click on the manner in the Saltwater Library of our site.
The type of live rock used is a mixture of Fiji, Indonesian and Marshall Island rock. In SPS corals the calcareous algae on this rock seem to disappear over time. This is attributed to the fact that the corals grow so well that they compete for availalbe calcium with the corallines. Even though Kalkwasser is added, the SPS corals appear to win the battle so to speak. Consideration is being given to add a Kalk reactor to the system to counteract this.
In aquariums with LPS corals and some soft corals, corallines grow in moderate amounts. This is a positive feature of the system according to Mr. Leng Sy as the glass or acrylic is not covered with corallines, needing cleaning on a regular basis to remove them.
Power Heads for circulation are used in the tank. The amount depends on the water motion requirements of the corals in the tank.
It is estimated that between 30 and 100 tanks using this type of filtration are now in operation.
Note that
Mr. Leng Sy started experimenting with this system in
1989 and has been perfecting the method ever since. We
are not talking about something that just came out of the
blue suddenly. Granted, some hobbyists will say: can we
really base a whole philosophy on a limited number of
tanks? 
This is indeed a valid point but the results and the commentaries on this type of filtration given by those who have seen it indicate that the results are indeed far superior to what they would have expected and that the amount of maintenance on these aqurariums is minimal.
Costwise they have an advantage of traditional live sand live rock aquariums as well since not that much Mud is required (30 pounds will run up to a 180 gallon tank with a heavy load).
Skepticism exists of course because so much goes against what we are used to do and how we are used to set up our tank (the fact that no skimmer is used is certainly a major one).
The success is however undeniable. The system delivers and works. I am going to set up an aquarium myself and have ordered MUD and hope to have it in next week. I will then be able to give you a running account of what actually happens. It will be set up exactly according to the specifications set forth by Mr. Leng Sy.
What is of course most interesting is that the Caulerpa grows and populates part of the sump and then stops growing after a while. Nevertheless nutrient levels in the tank stay low and water quality remains high. This is difficult for us to understand as we would expect that die offs would occur. According to Mr. Leng Sy they do not. More on this later though.
More in part III on additives, supplements, calcium, strontium and testing and further details about the system.
I asked Mr. Leng
Sy about testing. He replies: "I seldom test my
tank's water chemistry. Everytime I test everything shows
up at ideal readings. I gave up on testing. Never tested
for strontium. I don't really care that much because
everything is running real well I have tested for iodine
several times because I wanted to know why pumping Xenia
never crashed and do grow very well in my systems even
though I have never added iodine to the tank. The Miracle
Mud takes care of it all. 
My
test results for iodine were always around 0.05 ppm.
