Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   Water Chemistry (
-   -   Advanced Level discussion of filtration concepts (

bettababy 11-01-2009 05:10 PM

Advanced Level discussion of filtration concepts
I would bump the salinity up to 1.023 as most animals are going to need that level. Now is the time to add the live rock, but no animals until the tank is fully cycled. On average, a properly set up marine tank will average about 8 - 12 wks for cycling. In a 29 gallon tank I would suggest at least 25 - 30 lbs of liverock. The live rock will help aid in the cycling process. Be sure before adding the live rock that your temp is up to 76 - 78 and stable, and do not rinse the rock before putting it into the tank.

Expect some die off from the live rock once it is added, and that applies each time new live rock is added even if it is already cured. Live rock will suffer from die off to some extent anytime it is moved to new conditions. This die off will increase your ammonia levels, so don't panic if the ammonia spikes rapidly or to quite a high level. This is normal.

For a 29 gallon tank, finding a quality skimmer may be a bit of a challenge. Most of the top skimmer brands are made for larger tanks and will not fit on a 29 gallon tank.

You may want to check into something like a SeaClone or the Coralife brands of hang on skimmers, those are probably going to be your best bets for that size tank. The BakPak skimmers are very good but can take a bit of practice and time to get them adjusted properly, and they take up quite a bit of space. I'm not sure how you're set up, if a BakPak would fit for you, but its worth a look see.

Another option is the Skilter. I have heard good and bad about them, but my personal experience was actually very good. I ran a Skilter system on a 30 gallon for a number of years without issues, but it did require emptying the cup about once every other day. That will be dependent on your water chemistry and how much is being removed by the skimmer. Point is, I found it an effective option for a smaller tank. Fosters & Smith has the Skilters on sale right now for the next 2 wks, so it might be worth checking into.

JBJ has a small skimmer available for smaller (nano) tanks, but I have no info to offer on it as I have never used it or known anyone who has. Fosters & Smith offers each of the skimmers I have mentioned, so it should be easy to take a look to get names and manufacturer's info to research them all.

The one skimmer for smaller tanks that I dislike is the VisiJet and will warn you away from those right from the start. They can be very difficult to get set properly and are not as effective or long lasting as the others listed. VisiJet is the one that our customers always had the most issues with.

While hang on filters can work just fine for a small marine tank, you will want to keep up on wiping things down daily to avoid issues with salt creep. Hang on filters will provide some level of splash, and anything that the spray (even fine mist spray) comes into contact with will leave salt residue behind. Salt can be quite messy and destructive when it comes into contact with wood, fabric, carpeting, curtains/drapes, and drywall, etc. If left to collect the salt will eat through most materials rather quickly.

The other note about using hang on filters is to be sure to fill the filter boxes with plenty of bio medias such as sponges, noodles, etc. A marine environment will work primarily from biological filtration (the live rock also contributes in this way) instead of the typical chemical and mechanical that are so well known and often used in freshwater. You can even use small scrap pieces of live rock to put into the filter box as biomedia. The standard hang on filter medias are not appropriate for marine tanks in most cases. The Aquaclear sponge is already a great media, but should not be the only media in that filter. When packing the hang on filter box with biomedia, especially with an AquaClear, watch your water level and flow rate.

AquaClear filters when backed up, over filled with media, or when media becomes clogged, will overflow out of the back of the box. This also applies to the Skilter. Spend the cycling period playing with it until you get it just right and working for you, and doing as much research as is possible for the animals you wish to keep. Cycling is "prep time" which helps make that time go faster instead of dwelling on an "empty" tank.

Overall, continue with patience, that is the one single most important thing you will need throughout the process.

Hope this helps.

Pasfur 11-02-2009 05:42 AM


Originally Posted by bettababy (Post 267234)
The other note about using hang on filters is to be sure to fill the filter boxes with plenty of bio medias such as sponges, noodles, etc. A marine environment will work primarily from biological filtration (the live rock also contributes in this way) instead of the typical chemical and mechanical that are so well known and often used in freshwater. You can even use small scrap pieces of live rock to put into the filter box as biomedia.

This an issue that Dawn and I disagree on, always have and probably always will. My goal is to keep it simple and recommend solutions that are not only effective, but reduce the amount of time and energy you needed to keep the environment stable.

The use of biological filter media, such as bioballs and sponges, is my point of concern. These filters are extremely efficient at 2 things. First, they break down ammonia into nitrate. Second, they trap detritus, causing an increase in phosphates and a decrease in carbonate buffers. These are not things that I want to occur inside my aquarium.

If biological media were the only method for removal of ammonia, then this would be the technique that the hobby would use. Fortunately, there is a much easier and more efficient method of removing waste. This is the use of a protein skimmer and live rock, preferably accompanied by a deep sand bed system, such as the one being used in the aquarium on this thread. On aquariums that are set up with this type of filtration, the use of biomedia will DEGRADE water quality, by increasing nitrates, increasing phosphates, and reducing carbonates. All of these things require increased time on behalf of the fishkeeper to adjust.

wake49 11-02-2009 07:21 AM


Originally Posted by bettababy (Post 267234)
The other note about using hang on filters is to be sure to fill the filter boxes with plenty of bio medias such as sponges, noodles, etc. A marine environment will work primarily from biological filtration (the live rock also contributes in this way) instead of the typical chemical and mechanical that are so well known and often used in freshwater. You can even use small scrap pieces of live rock to put into the filter box as biomedia.

Filter media, because of its size and orientation, cannot harbor anaerobic bacteria. This is one of the most important forms of bacteria in Marine Aquariums. We rely on Live Rock and Live sand for this bacteria. Anaerobic bacteria live deep within the rock and sand, feeding on broken down Nitrates. This is a part of the Nitrogen Cycle and very important in the Marine Aquarium hobby.

Live Rock and Live Sand as filtration is coupled with the use of a protein skimmer. Protein skimmers pull organic acids out of the water before they are broken down into Nitrates and Phosphates. Nitrates and phosphates are bad because they are the main foods for nuisance algaes. Protein Skimmers use the same concept as crashing waves to pull out organic acids. These crashing waves create a foam, and protein skimmers try to re-create that foam. The bubbles of the foam attract organic compounds, and the result is the sludge in the skimmer cup. Of course the ocean also uses algae as a filter, and people replicate this by putting macroalgae in their sumps and refugiums.

Click Here to read more information on types of filtration.

Filter pads collect those organic acids (detritus, uneaten food) and they break down again into nitrates and phosphates. You either have to clean that filter pad every day, or just take it out. Since you have no fish in your tank as of yet, the filter pad can't be too dirty.

When I used Live Sand and Live Rock to cycle my aquarium, I was at stable levels within a week. I still did not add fish for a few weeks, as I waited for a diatoom bloom to come and pass. Diatoms will look like an ugly, rusty type of algae, almost like particles grouping together (if anyone can provide a better visual, please do. I'm not the greatest at painting mental pictures, lol). After that had passed (for the most part), I had begaun to add fish.

I strongly disagree with the use of filter pads, bio-balls, filter floss or anything of this concept. There is just no way they can harbor the correct bacteria for denitrification. All the studies done and literature written in the past twenty years supports Live Rock, Live Sand and Protein Skimming as the ONLY forms of filtration in a saltwater aquarium.

bettababy 11-02-2009 02:01 PM

I have not yet touched on denitrification, I was still focused on nitrification. While the skimmer pulls out organic waste, it does not remove the ammonia that the fish are putting out all the time. The ammonia is still present, needs nitrifying bacteria to break it down to nitrate, before it can be removed via one of many methods (natural biological denitrification or the use of filter medias).

By adding things like sponge and live rock to the filter box, we are promoting the colony of nitrifying bacteria, much the same way we do in a freshwater environment. Some types of live rock are very dense, which means they provide limited surface area for nitrifying bacteria to grow. The sand bed will offer a good surface area to a certain depth, provided it gets enough oxygen for the bacteria to grow and thrive, and even the inside surfaces of the glass and filter parts. Surface area is important to get the cycle started. A sponge or other bio media in the filter box will perform the same function... to provide surface area.

To simplify, nitrifying bacteria need plenty of O2 to thrive and live, denitrifying bacteria need little to no O2 to thrive and live. Nitrifying bacteria create nitrate through their feeding/waste production process. Denitrifying bacteria feed on nitrate to remove it via their waste product as gas exchange.

Yes, sponges need to be rinsed out regularly, which is more work than some people are willing to do. In that case the use of live rock scraps, bioballs (which I'm not real fond of, but they work), and things like the Eheim noodles can make a good substitute and will not need to be continuously "cleaned". Nor will they trap the bad stuff that has thus been mentioned here so far. The sponge will also help to collect solid waste particles in the water column, things that a skimmer will not remove. (A skimmer will only remove organic waste that can make it to the surface with the bubble agitation) I have never found the regular cleaning of the sponge to be an issue or too much work, but that is an individual opinion.

When it comes to denitrifying bacteria, the sand bed must be deep enough so that it is not saturated in oxygen. This is the reason many people set up a refugium. When nitrate is broken down, the end result is nitrogen gas, in the form of bubbles that build up in the sand and eventually rise to the surface, where they break and release the gas in a harmless fashion. This process requires the substrate not be disturbed which would allow oxygen to make contact with and destroy the bacteria culture. If these gas bubbles are being released into the main tank, as they rise to the surface they decrease in size as the gas is chemically released into the water column on the trip to the surface. (Think of the way a CO2 system works and you get an idea of the chemical breakdown/process)

In my post I had not yet approached denitrifying bacteria because we have as of yet to get to that step, as we have no nitrates to feed that bacteria yet. I was trying not to overwhelm because I know my posts sometimes get very lengthy and I try to offer as many details as possible to promote easier understanding. I apologize if I gave a wrong idea/impression by not including the end process of the cycle thus far.

But, in ending, I would like to say I stand on the things I suggested, use these methods myself, and have taught them to others for many yrs with a wonderful success rate. My current reef tank is about as maintenance free as an aquarium can get... I add water when it evaporates, I add food every other day, and I trim out the red grape caulerpa weekly because grows at lightning speed. Once/month my husband dumps in his chemical mix to promote coraline growth, but this results in my needing to scrape the glass regularly to remove the coraline algae just so I can see through the tank. That is all I do. My mushrooms are reproducing at such a rapid rate, I went from 3 to 30 in less than 3 months. The hammer coral came to me with 2 branches, 3 months later I have 5 branches and new ones budding everywhere. I rely completely on biological filtration in this tank, as I have all of my marine tanks since I began keeping them almost 20 yrs ago now.

I can agree to disagree with anyone, even you, Pasfur. There are many different methods that work. I prefer natural and easy, so is what I try to teach to anyone who wishes to learn. What works for 1 person will not always work for another, and sometimes a person isn't able to understand 1 method but understands another or has some materials available and others that are not. We all come from different places around the globe. Weather, water quality, and product/animal availability differ everywhere.

I think the best approach to helping anyone with something like this is to offer many methods that work and let the person decide for themselves which one they grasp better, works for them better, is least expensive for them, or the least amount of work they are wanting to do based on products and animals they have available to them (or money). So lets please not debate, but instead share all of our knowledge freely and openly.

It is the sharing of knowledge that advances knowledge and always keeps us inspired to learn and understand more.

Pasfur 11-02-2009 06:36 PM


Originally Posted by bettababy (Post 267639)
I have not yet touched on denitrification, I was still focused on nitrification. While the skimmer pulls out organic waste, it does not remove the ammonia that the fish are putting out all the time. The ammonia is still present, needs nitrifying bacteria to break it down to nitrate, before it can be removed via one of many methods (natural biological denitrification or the use of filter medias).

I agree to a point that debate can be counter productive. However, there is a time for an honest discussion of basic principles. Without such discussion, the hobby would never advance. I want to state this next point for anyone who is reading. BettaBaby, your experience and knowledge are EXTREMELY appreciated and desired here. I have nothing but respect for the skills you bring to this forum.

That being said... 8)

The above statement is incorrect, and I believe is the root cause of this debate. Marine fish do not release ammonia into the water. Freshwater fish release ammonia. Marine fish release various organic compounds that only become ammonia when they become caught on a surface which is active with bacteria, such as biomedia or filter pads.

onefish2fish 11-03-2009 01:27 AM

any filters with media, even the sponge over pumps or skimmers collect debris and detritus at a fast rate and contribute to the water quality. you could do it but they would have to get cleaned to frequent to be worth it let alone the frequent cleanings would wash away any "good bacteria" anyways. the live rock in the tank, if theres enough will provide enough space for your beneficial bacteria. putting live rock rubble in filters and even sumps can trap things just like a filter would.

bettababy 11-03-2009 04:00 AM

Ok Pasfur,
I have spent my night here with my nose in the books looking this up just for you. I bring references and will list book title, author.. and locations of the quotes I bring to you. I figured 4 different books/authors would be enough to explain things and make the point, especially considering one of them is a college text book and another is authored by names that should be easily recognized here. Feel free to look these up for yourself.

The Living Aquarium by Peter Hunnam, Annabel Milne, Peter Stebbing

Pg 138 section of Biological Processes
"Third, the primary waste products of animals metabolism - notably ammonia - are toxic to most animals and must be minimized, since they are excreted into the aquarium water."

Pg 173
"Excretion, secretion, and decay of organisms result in abundant particles of detritus, dissolved organic molecules (carbohydrate, protein, and fat fragments), and dissolved ammonia in the water."

The Tetra Encyclopedia of The Marine Aquarium
by Dick Mills
Consultants: Dave Keeley, Terry Evans
Tetra Press No. 16059

Pg 24
"Once water has been 'lived in' (for want of a better phrase), the resultant effect of the waste product of fish respiration, digestion and natural decay on the water quality can be measured. The main component of waste products is ammonia, together with two other important nitrogenous compounds, nitrite and nitrate."

Volume One The Reef Aquarium
by Charles Delbeek and Julian Sprung

Pg 133 - 134

"When a fish passes ammonia across its gills into the surrounding water, or defecates, these products do not simply seek the trickle filer underneath the aquarium."

Text Book - Fishes An Introduction to Ichthyology
3rd Edition
by Peter B Moyle, Joseph J. Cech, Jr.
Department of Wildlife, Fish, and Conservation Biology
University of California, Davis

Pg 103 - 105
"In teleosts, these nitrogenous wastes take the form of ammonia, a potentially toxic substance."

"Despite its toxicity, ammonia has many advantages over urea or uric acid as the chief excretory product of nitrogen metabolism as long as the animal resides in an environment with abundant water. First, the small molecular size and high lipid solubility permits un-ionized ammonia (NH3) to diffuse easily across the gills. Second, ionized ammonia (NH4) is exchanged for Na+ at the gills for maintenance of relative alkalinity and internal ion balance. Third, conversion of ammonia to either urea or uric acid requires energy. Thus in contrast to terrestrial forms, less energy is required to complete nitrogenous compound catabolism and, in teleosts, the end products resulting from this catabolsim are largely released at the gills rather than the kidney."

Sorry,but I must stand on what I posted earlier. I'm not trying to be difficult, only to be sure you understand that I am not guessing about the information that I posted.

Pasfur 11-03-2009 05:15 AM

The difficulty with such references lies in the context. The question lies in what information is attempting to be communicated, and how detailed the information needs to be to express the point being made. I can only assume the material was being presented at a "high level" summary, or that the term is "ammonia" is being used to express a concept.

I will make an effort to find a reference for you. It is clear that the usefulness of a protein skimmer would be obsolete if ammonia was directly released into the water, as ammonia does not bond to the bubbles in the skimmer shaft. While there is no doubt that some organic waste breaks down to produce ammonia, this is why we have live rock and live sand, as I believe Wake explained above.

Interestingly, even if we take at face value that ammonia is a primary excretion, it does not change anything. We would still be recommending live rock and sand as the method of ammonia removal. There is simply no logical reason to intentionally introduce nitrate, and to some degree phosphate, into a marine system.

wake49 11-03-2009 02:22 PM

The process of respiration in fish is the biggest contributor of Ammonia is any aquarium, marine or freshwater. Here's a reference. As fish breathe in water, they use the oxygen. Excess Hydrogen ions are attracted to excess Nitrogen ions in the fish's system (what they consume in foods but don't use) to form NH3 (Ammonia). So fish pass both Carbon Dioxide as a byproduct of respiration, and ammonia as a way to excrete excess Nitrogens. This NH3 is attracted to H+ ions to form NH4+, or ammonium ions. These are the two types of ammonia present in the home aquarium.

The job of Live rock is to break down these ammonium ions and ammonia in the water to Nitrites (NO2) then to Nitrates (NO3). This is Nitrification. The basics of the Nitrogen cycle, and the most important part to maintaining balanced water. These nitrifying Bacteria can be found in Live Rock, Live Sand, Filter pads, Bio-balls, and all other forms of places where a bacterium can reside and flourish. Algaes and other photosynthesizing creatures in the aquarium also consume Ammonia and ammonium ions, depleting its content in the water.

The problem with those filter pads is again the aforementioned de-nitrifying bacteria. It is anaerobic and resides deep inside the rock and deep below the sand surface. This is the bacteria that safely converts Nitrates to Nitrogen gas, which escapes the system naturally. Both a filter pad and Live Rock contain aerobic bacteria, but only the Live Rock (and a DSB) contains the anaerobic bacteria necassary to complete the Nitrogen cycle in the home aquarium.

So why not filter pads, and double the aerobic bacteria? Because as mentioned by OF2F and Pasfur, these are nutrient traps. Constant cleaning only means that you are killing these colonies of bacteria. Don't clean it and food particles and organic waste and other nasties break down to Nitrates and Phosphates.

The Protein Skimmer works independantly of the bacteria, pulling organic compounds (produced by the fish as waste excrement) out of the water before it can break down. Activated carbon does primarily the same job.

But here is a large factor that is for some reason NEVER mentioned in this debate. FLOW!! Even utilizing the Berlin Method (Live Rock, Live Sand and a Protein Skimmer), detritus or uneaten food can settle on the rock and start to clog the pores of the rock. Now the anaerobic bacteria is useless, becasue it can't feed off the products of the aerobic bacteria. There need to be no dead spots, and particles must stay in enough suspension in the water column to be picked up by the skimmer. And as a personal belief, I like to have animals in the tank that pick at the rocks looking for food. Algae Blennies, Gobies, Tangs, crabs, snails...etc. I think that they help to keep the rock surface disturbed enough to keep the pores of the rock clean.

I hope that we can see that both BettaBaby and Pasfur bring strong points to the table. I would personally never use filter pads, bioballs or any media of that source. It is a nutrient trap. And unnecassary, as Live Rock will do a better job at the Nitrifying process.

bettababy 11-03-2009 04:20 PM

I added some photos to my album section since the ones in my aquarium log don't appear to be working properly. There is only 1 tank in there right now, my 29 gallon reef. Filtration is simple... there is live rock in the built in sump. This tank thrives and I do no real work of any kind to accomplish this. If what is being suggested here, that by using live rock in the filtration system only serves to trap organics, then this tank should not be in such good condition. There is no skimmer on this tank, no hang on filter, no canister... and no other media than live rock. This is not the first tank I have kept this way, and all have the same results... they thrive. My husband's 120 ran a sump, skimmer, and refugium, and in the sump were no medias other than bioballs and live rock.. and it, too, thrived with no real maintenance other than feeding it and topping off water levels once a month or so. I have never put chemicals into my tanks, no nutrient or elemental extras, and the water chemistry has changed in the various places I've lived... still nothing special has ever been needed. The only time I've had marine tanks that require any kind of work is anything 10 gallons or under due to evaporation rates.

We will have to agree to disagree at some point here. I have to stand on what I know first hand after yrs of experience... works without issue, works without the demands I hear so many go through to have a healthy and good looking tank, and works without the extra expense I see others experiencing.

As for the quotes I offered, I ask you to seek out at least one of those books and reference the page numbers I listed, and to read through the entire chapter, or book if need be. Those quotes were not taken out of context. I was not about to write out an entire chapter for you to get to the quote that directly applied to what we were discussing... that marine fish do indeed excrete ammonia into the aquarium water. Based on that concept, nitrifying bacteria are still just as much in need and are still the beginning phase of the nitrogen cycle... and that denitrifying bacteria need the food created by the nitrifying bacteria in order to survive.

I am not trying to knock the use of a skimmer, or all the other natural methods there are to keeping a marine tank healthy and thriving. I promote the use of a skimmer, especially to a newbie. That is a wonderful piece of equipment... and it can mean the difference between success and failure in some cases. But there are things the skimmer can't remove, and those other things, such as ammonia, need to be accounted for with biological means, mechanical means, chemical means... whatever makes the individual happy. Adding live rock to a hang on filter has never caused me an issue, either with or without a skimmer on the tank. I know many others who have accomplished the same thing the same way, and I have been teaching these methods for many yrs.

Now that the info is out here, and has received many points of view, it is up to the individual to use the method that works best for them.

All times are GMT -5. The time now is 04:22 AM.

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0 PL2