Lets Talk About ~Filtration Concepts~

[aquariumdebacle]

$.02-%50off,

The important thing to remember is that what goes in must come out. The protein skimmer and water changes are the two best means of true export. Once it's in the skimmer cup/bucket it is effectively removed from the system and no longer contributes to the nutrient build-up.

Canister filters and back filters are the worst of these because until the filter is cleaned the nutrients remain to be used. These must be cleaned diligently.

Deep Sand Beds and Refugiums work more like Rain forest canopies. The nutrients are bound up in the living tissue of the animals and plants in the system. While the creatures are alive the nutrients are unavailable until eaten by the animals. The key to this system is diversity and numbers of creatures. More is better. The laws of thermodynamics takes place as each step of the cycle consumes a small amount of energy and is released as heat through respiration. Volume is key here; the more volume of water,DSB, refuge, etc. the better the system works

The U.V. sterilizer is not very effective unless it is extremely oversized and at least 5 micron filtered before it reaches the light. the kill ratio is defined by dwell time (rate of flow) and intensity (light wattage.) It should be used in conjuction with other filters. It is not a good preventative tool as the light can get covered with film over time as the light fades. Change the bulbs regularly and clean the system often. Use it on a hospital tank.

The ozoner is a very effective (too effective without a controller) way to increase the redox level of your system. Used in conjunction with a protein skimmer this can really clean the water. Be careful as ozone is not good to breath. Filter the air coming out of the skimmer through carbon. This is where the coconut shell carbon is superior.

The oxidation-reduction equation is what all of this talk is all about. Certain processes oxidize (respiration) and other processes reduce (photosynthisis, chemotrophic bacteria.) This equation is really just a transfer of electrons. The problem in the enclosed system is that the oxidation far out-weighs the reducing capacity of the system.

Reducing our systems will help keep our animals in good health.
Got that all you nano-reefers!

 

[mojoreef]

Hey Dan good to see ya back online again.

The nutrients are bound up in the living tissue of the animals and plants in the system.

Hmm I think your missing a whole lot more stuff here, DOC's, inorganics, detritus and so on. but lets save that for the DSB system (we can do that next).
UV's are are basically used as a disinfectant and I believe can play an important roll. If plumbed properly they can take out a host of pathogenic protozoa and other infectious bacterias.

Great post Dan


Mike

 

[jks1]

Ive read alot of conflicting info on UVs. I personally run a 25W on my 210g with a flow rate through the UV of ~300gph. Is there a recommended range for watts to gallons and corresponding amount of flow?

 

[NaH2O]

jks1 - I found the following quote from this site UV Sterilizer Overview:

Flow Rates:
The recommended flow rates and required wattage for tanks may not seem consistent between manufacturers. The Emperor 25 Watt UV Sterilizer is rated for 125 gallons. The Aqua Ultraviolet 25 Watt UV Sterilizer is rated for tanks up to 100 gallons. The Rainbow LifeGard 25 Watt UV Sterilizer is rated for 200 gallons. The Coralife 18 Watt for 250 gallons. The Custom SeaLife 18 Watt for 100 gallons. Some of this may be because the manufacturers are measuring things differently. For Example: Emperor Aquatics' recommended flow rates are based upon when UV Sterilizer lamps are operating at their 60% end of life efficiency. Additionally, flow rates may be comparing apples and oranges because they may be referring to the effective kill rates of different organisms.

This site recommends as a generalization that: 8-9 Watt = up to 55 gallons; 15 Watt = 55-100 gallons; 25-36 Watt = 100-150 gallons; 40 Watt = 150-250 gallons.

 

[clownnrnd]

So Mojo if I understand you correctly you are saying that you run phosphate remover on your system at all times. If that is the case do you test for phosphates periodically to see when phosphates begin to rise and use that as a indication of when to change the media? or do you just replace it on a schedule?
Thanks,
Chad

 

[fishermann]

jks1 I put my bags in a bucket and on the weekend i turn them wrong side out and give a quick rinse and thow them in the washer on gentle with warm water. Jeff at shark reef said to run through twice so if there would happen to be a soap residue left from the wife washing the second time through for sure would be soap free. The second one i do for a much shorter cycle, have never had my wife complain about any left over effects. I have done it this way for a year and a half now. After a year i get new bags. I run phosban and uv 24/7, also chem-pure carbon.

 

[Montanarocknreefer]

An example of this would be John Saxby, he has a large thousand gallon tank, but he has over 500 fish in it. The only way he can do this is by having a system that effectively deals with the detritus/waste/left over food.

So Mike are you saying we can get away with having more fish in a BB system than a DSB system?

I would think the size of the tank, swim space and compatability with each other will also determine the number of fish you can keep in any system. Also alot of fish require a sandbed for burrowing as well.

I do understand that you need to export the nutrients out of the system as soon as effectively possible.

I like the idea of having very small fish in system not only for what they will release into the water but will make the reef seem bigger in a smaller tank.

How do you feel about having alot of water flow running while feeding your tank? Should we keep the flow constant or turn off for an hour or so during feeding as I have read from alot of different sources.

With the water flow you have designed for my 60 gallon cube tank, I am assuming I will still need to blast the LR from time to time(which I consider very beneficial to corals and as you say to reintroduce food back to the tank for fish, etc.).

So as long as you can effectively remove all the detritus from the system in a short period of time than size of tank does not become an issue with a BB set up?

So Mike as you have mentioned before, even have a bare sump is also a very good thing as you don't want detritus building up there as well. So what about running a BB system and then having rubble rock/macro algae in a sump? We know the rubble rock will be a collection trap for sure.

I am anxious to see how great a BB system is as long as you do good husbandry practices.

 

[NaH2O]

Origianlly posted by Montanarocknreefer
I am assuming I will still need to blast the LR from time to time(which I consider very beneficial to corals and as you say to reintroduce food back to the tank for fish, etc.).

Johnny, no matter what type of flow, detritus is going to collect, so blasting the live rock and other settling areas from time to time will be important. If you think about your tank like your house....the air flow from vents, open windows, etc. allow dust bunnies/animal hair to collect in certain areas (like under a couch, in corners, etc). If you took a fan and walked around blowing the areas where the dust bunnies collect, you will free them to be sucked up by the vacuum (really bad analogy ). Same thing for your tank. Think about the crevices in live rock....detritius will be happy to settle in there and some other areas of the tank - it is unavoidable. There will always be areas that flow isn't enough to prevent settling of detritus. Also, IMO, it is more important to think about getting the detritus in the overflow and skimmed out, rather than as a reintroduction of food.

Originally posted by Montanarocknreefer
even have a bare sump is also a very good thing as you don't want detritus building up there as well. So what about running a BB system and then having rubble rock/macro algae in a sump? We know the rubble rock will be a collection trap for sure.

You really don't want detritus building up anywhere. If it does, it will just begin breaking down and fouling the water. The rubble rock will definately collect detritus - just make the sump maintenance part of the tank maintenance routine.

Good questions, Johnny - great post

 

[Doug1]

Johnny, no matter what type of flow, detritus is going to collect, so blasting the live rock and other settling areas from time to time will be important. If you think about your tank like your house....the air flow from vents, open windows, etc. allow dust bunnies/animal hair to collect in certain areas (like under a couch, in corners, etc). If you took a fan and walked around blowing the areas where the dust bunnies collect, you will free them to be sucked up by the vacuum (really bad analogy ). Same thing for your tank. Think about the crevices in live rock....detritius will be happy to settle in there and some other areas of the tank - it is unavoidable. There will always be areas that flow isn't enough to prevent settling of detritus. Also, IMO, it is more important to think about getting the detritus in the overflow and skimmed out, rather than as a reintroduction of food.



You really don't want detritus building up anywhere. If it does, it will just begin breaking down and fouling the water. The rubble rock will definately collect detritus - just make the sump maintenance part of the tank maintenance routine.

Good questions, Johnny - great post

Getting the detritous out of the tank is the key. The storm effect of suspending it allows that hopefully. The organisms exposure to it as food is a collateral benefit and only a small factor in the equation. Once you accept that an abundence of phosphate in it's various forms is what drives the runaway growth of algaes, cyanobacteria and other stuff we don't want,it's easy to see why removing food and detritous as soon as possible is the key to success. Another benefit of a BB tank with enough flow to ensure removal of most of the detritous, as well as decent maintanence is that you should be able to support a larger fish population, at least from a waste management standpoint. Theoretically with waste removal, open sump,skimming, and vigorous areation , the O2 saturation should be able to support a few more fish, however keep in mind that with SW fish territorial imperative also plays an important role.
The analogy I have evolved is a comparison between a garbage disposal and wastecan(frequently emptied) and a utility room that all the trash and garbage is thrown into, where rats and roaches and various other vermin feed on it. Which would you rather have

 

[NaH2O]

I'd like to add a couple of cons to the mix. One con is obviously aesthetics. Nothing you can do about it - you have to set-up your tank so it is appealing to you. Another con is keeping sand loving fish without having some type of "sand box" for them.

 

[Montanarocknreefer]

Thanks Nikki and Doug for your input! I think I am beginning to understand this alot better. Mike you have done your part in sinking this into my thick skull!

 

[mojoreef]

Well Johnny I think Doug and Nikki nailed down your questions pretty good. When looking at filtrations systems you have to keep the concepts in mind on all systems. Having a good understanding of the concept will make it very easy to operate it no matter which system you choose to go with.

Ok so the concept of Bare Bottom systems is to remove the detritus/waste/leftover food prior to is degradation/reduction, thus less biological filtration is required (ie sand) as you are bypassing that stage completely. Exportation via a good protien skimmer and other means are employed.

lets move on to another filtration type system.

Mike

 

[Montanarocknreefer]

Ok Mike what type filtration is next? DSB?

 

[mojoreef]

OK let's move on to deep sand bed systems.
The concept of a deep sand bed is to create an environment skewed to the population and growth of various bacterias. These bacterias will reduce and or cycle various elements of food/detritus/waste.
There are numerous cycles which occur in a deep sand bed, i.e.: nitrogen/phosphate/carbon/sulfur/iron and methane cycles. The cycles utilize most environmental types created by a deep sand bed. The deep sand bed can be broken down into zones. The first so is the aerobic zone (oxygenated) in the second zone is the anaerobic (depleted oxygen) and the final zone is the anoxic (devoid of oxygen).
The first zone of a deep sand bed is called the aerobic zone (oxygenated). In this zone a variety of creatures live, snails, pods, various worms and so on. But the most important critter is bacteria. In this zone bacteria will reduce ammonia to nitrite and nitrite to nitrate. This process is called nitrification and is done by the stealing of a proton or electron from nitrogen based products.
From here through the migration of worms and so on nitrate is passed down to faculative bacteria(batceria that can fix both oxygen and nitrate). As oxygen levels deplete these bacterias change from fixing oxygen to fixing nitrate. Nitrate is reduced nitrate oxide then reduced to nitrous oxide and finally reduced to dinitrogen gas. This gas is then off gassed back up through the bed and into the water column. However if there is the presence of ammonia anywhere in this is all been expectation will not occur, instead nitrate will be converted to ammonium which will then migrate up to the aerobic so and once more will be reduced to nitrite and then back through the cycle once again.
The carbon cycle basically boils down to respiration. Carbon dioxide is reduced via certain cycles to for glucose which is used as energy. This will provide a certain amount of exportation, usually about five to 10% of whatever the input is.
The sulfur cycle occurs in both the aerobic and anaerobic zones. Here the sulfate portions of food/detritus/waste our reduced to sulfur and then to sulfide. Sulfide can be reduced further to sulfide gas in the anaerobic zone. All sulfur products will not be exported but will be continuously cycled with in the sand bed.
In the phosphate cycle the phosphate portion of food/detritus/waste enters the sand bed. It is immediately attacked by bacteria trying to reduce it. With this influx of food the bacteria population will bloom. As the food begins to be reduced and is no longer available the bacteria will begin to die off, once they do this the phosphate that they had fixed is released back into solution. Here usually algae is the first organism to take advantage of this. Cyanobactor and hair algae are usually the first on-the-job, they utilize the available soluble phosphates and begin to bloom themselves, this will continue until they use up all the available food stock. Then once again they begin to die off, at this point bacteria begin to reduce the rotting algae and once again bloom. What you will see is small blooms of hair algae and or cyano appear on your sand or adjoining surfaces, it will then disappear as it is reduced. As you continue to add more and more phosphate to your tank these blooms will get larger and larger until they will not disappear.
The balance of the cycles that occur in the sand bed usually do not have an impact on its health.
The deep sand bed is usually set up by using four to 6 inches of oothlic sand. Oothlic sand is very fine and allows more surface area for the growth of more bacteria. Detrovior kits must also be added to the sand bed. These kits consist of bacteria, worms, snails, pods and so on. These critters are essential to keep the sand bed stared and allow for the migration of food products to various levels in the sand bed. Creatures such as sand stirring stars, gobies, qukes should not be used in a deep sand bed system as they will eat and deplete the smaller above-mentioned critters. Natural selection will also deplete the stock of those smaller critters over time, so these kits should be added to the sand bed every eight to 12 months.
Pros:
if set up correctly and maintained correctly the deep sand bed system will allow for good nitrification and denitrification.
A deep sand bed environment will create a good refuge for smaller organisms such as bacteria, plankton, nekton and larva. Which can be a food source for higher life forms in the immediate area.
A DSB is aesthetically pleasing to many people.
A DSB will add more microscopic diversity to your reef tank.
A DSB will facilitate the harvesting of hair algae and cyanobactor on the sand substrate and adjoining areas. If this algae is harvested it can be a source of exportation.
Cons:
Since a DSB will only export nitrogen based products if set up correctly all other products that enter it will be sunk and stored. This will put a time limit on the functional ability of the sand bed as time goes by.
Since the sand used in setting up a DSB is already saturated with phosphates in the lower regions of the bed with a pH is very low the sand will begin to melt and release these bound up phosphates back into solution. This will also occur through bacterial action. So it will become a source of phosphates as it matures.
With the use of small fine sand, the amount of water flow will be restricted to whatever will not allow the sand to stir up into the water column.

Anyway I probably miss some stuff but it's a good start. So lets talk about it some more.

Mike

 

[szidls]

mike,
What is involved in maintnence of a dsb other than adding the service packs to the areobic sand layer? Is there a time frame for the usable lifespan of a dsb? I suppose it depends on a large portion of what animals you are keeping in your reef. If you have a large bioload of fish etc. ? I see many reefers are getting rid of dsb's because of phosphat issues. Is it worthwhile to replace a dsb after it is saturated?
Scott

 

[mojoreef]

What is involved in maintnence of a dsb other than adding the service packs to the areobic sand layer?

Well Scott one that really depends on who we are talking to, the experts say nothing else is required. However if you read the above breakdown of how it works you can see that you still need a large amount of exportation in order to take care of all the products that are not nitrogen based. In talking to some of the folks that have had longer term success (four to five years) they use all the same exportation devices as a BB system. However since they can't have any flow directed at the sand bed they usually stir the sand up (just the top inch) manually and siphon out the detritus and so on that is accumulating their. This seems to help in extending the life of the bed.

Is there a time frame for the usable lifespan of a dsb?

yeah this is a tough question, it really does depend on your feeding habits, your bioload, the types of additives you use, the types of salt mix is that use, and the kind of maintenance that you perform. So really hard to nail down a time frame. I personally have only seen a small percentage of DSB fail due to complete clogging. What usually happens to folks is one of two things.
1. They get tired of the continuous phosphate cycle and the associated algae blooms that come with it.
2. Or the bed forms a clog line due to heavy feeding, or even cycling of uncured live rock on a fresh sand bed. What happens here is all the die off from the live rock or heavy feeding/event saturates down into the bed and does not allow for the migration of other products down to the lower regions of the bed whether it be to sink or to cycle them.

Is it worthwhile to replace a dsb after it is saturated?

this one again is open to personal opinion. So here is mine. If set up properly and maintained properly the DSB can make a decent filter/sink. I would manually stir the top inch and site that off as much detritus/food/organics as possible manually in order to give the bacteria a chance to catch up on the reduction of whatever I could not siphon out. I would not be so reliant on critters such as worms/snails/so on and so forth but would rely more on mechanical means. Once I reached the point to where my mechanical siphoning was no longer winning the algae battle I would completely remove the bed. Replacing small sections of the bed or siphoning down sections of the bed to me are just asking for disaster. Now this goes against most popular beliefs on how to operate the DSB, but from my experience if I was going to go with one this is the way that I would do it. But also I believe them to be too much work and the thought of having to replace it one day is something I would not want to do again. But that's just my opinion. Let's see if we can get some more from folks that have had long term success with the sand beds.

Mike

 

[NaH2O]

Mike, I'm not real clear on what conditions would make nitrate convert to ammonium instead of reducing it to nitrate oxide.

What is involved in maintnence of a dsb other than adding the service packs to the areobic sand layer?

Scott, the original idea, if I'm not mistaken, behind DSBs was "set it and forget it".....the bugs and bacteria will take care of the detritus/food/waste. Personally, I think stirring up the aerobic layer to free up the detritus is good practice, however many would debate this. I believe the argument is you are taking food away from the sand bed critters which are key. You would also need to export nutrients via cyano and hair as it grew.

Is there a time frame for the usable lifespan of a dsb? I suppose it depends on a large portion of what animals you are keeping in your reef. If you have a large bioload of fish etc. ?

Exactly. The smaller the bioload, the less waste/detritus/food will be sunk into the DSB, so it won't become saturated as soon as a large bioload. It is hard to say exactly how long the DSB will be viable. No two systems are the same, so you can't really compare from one tank to the next, however, maintenance and husbandry could possibly allow it to last longer. How much you feed, what types and quality of food introduced, maintenace routine - all play a role.

I see many reefers are getting rid of dsb's because of phosphat issues. Is it worthwhile to replace a dsb after it is saturated?

Tearing out a DSB and leaving it out is a personal choice, as is replacing one. If a DSB has become saturated, then IMO it is time to take it out. However, if you really like having a DSB, replacing it with a new one would be fine. Add a scoop from the current bed to seed it, or prior to removing the saturated bed, cycle your new sand in a container.

I've often wondered how do I know the number and diversity of critters required to get a DSB to properly function.

Understanding the way a DSB functions, IMO, will help you know what to expect in the future, and how to deal with issues as they arise.

 

[NaH2O]

WOOPS...looks like I was late getting my reply in....guess I should go back and read

 

[Montanarocknreefer]

Well I had a DSB for three years in my 80 gallon reef tank. My tank did pretty well but where I failed miserably was good husbandry! A very key point in the success of a DSB but even at that it will have to be replaced at some time depending on what has been mentioned: bio-load, detrivore kits, water flow and many other factors.

I for one was under the impression that put in a DSB and you got it made! I got caught up in the DSB roller coaster and I have to say a DSB is not a bad thing but you have to remember how to care for it and know that some day it will need to be replaced. I choose not to go through that again and now sitting up a high energy flow cube tank with a BB bottom and excellent skimmer. Secret to a very healthy reef tank is get the detritus out of your system as soon as possible by blowing off the LR, stirring the top layer of the DSB and have great flow system and skimmer. By getting the detritus suspended in the water column it gives the fish and corals more chances at the food, etc and then out of your system now. It will make your water quality alot better and reef tank maintenance alot easier and enjoyable in my opinion.

 

[mojoreef]

Mike, I'm not real clear on what conditions would make nitrate convert to ammonium instead of reducing it to nitrate oxide.

Nikki as I mentioned before bacteria cannot eat or reduce things directly they need to basically melt their food with the use of enzymes. If there is ammonia present in the anaerobic zones the ammonia it self will inhibit the production of the first enzyne used in denitrification. Without that enzyne denitrification cannot occur, so nitrate is then just converted to ammonium and continuously cycled. This is what is happening with the Jeaubert Plenum system in Monaco.


Mike