Tank turnover theories

I’ve noticed when reading articles and care sheets about different types of fish, and also on Internet forums people often mention minimum times you should turn over the tank volume, often ridiculously high ratios like 10 times the tank volume are quoted, to me it seems without any workings or science to back this up.

While I agree with the general consensus that more filtration is never a bad thing (unless you have fish that struggle to swim in a lot of movement) but I’m interested as to why a certain flow rate would be needed in an aquarium? If your filter has enough media to handle the bio load, and you have sufficient aeration/movement, I struggle to see why anyone would strive to achieve 300 gallons of flow an hour in say a 30 gallon tank, or even 5 times the volume. Seems a bit like the inch per gallon rule to me, something people quote without really knowing too much about it. I can see why in heavily planted tanks it’s more important, but African cichlid keepers seem to think it’s very important and they don’t have plants.

I’d like to know people’s thoughts and theories on this, as it’s something I completely overlook, after all my mechanical filtration, bio media and pipes, my canister filter only has an actual output of about 40% of the manufactures quoted flow, which is about 2.5 times the tank volume, but as far as I can tell it still easily handles (no ammonia or nitrite) the bio load in quite heavily stocked tank.

 

The video is a way of selling his product all around the world to people trying to do the right think as they start in the hobby.
I have a couple of kilos. It’s holding together ok after 4 years. I don’t think it’s that special ? It not dissimilar to any other good quality ceramic media. I read recently just how many kilos per litre of water are needed and thought now you tell me. The blocks/ sausages are not all exactly the same size and do not stack particularly well in small filters.

 

There is some truth in what PondGuru is saying. However, you have to realize that his video also serves as an infomercial for the BioHome filter media he helped develop and is trying to sell for monetary gain. As long as you realize his motives and are OK with them, that is fine.

I'm a born hobbyist RC, and I have a deep admiration for honest entrepreneurs. Pong Guru was obvious about his personal considerations from the start, which I admire as well. The fact that his products are SOTA, and verified as such, is the only factor that's important to me. I mentioned my status as a flaming hobbyist, so you'll hopefully understand my mindset to the highest degree possible. My intent in telling you this is to ease tensions and make it easier for you and I to converse and exchange relevant data, if need be.

My intention is to create a nitrate reactor out of one of my filters. Once I absorb what I can from PG's content and Pfrozen's excellent post, it should be easier than I had anticipated. I'll start this journey with a question: Is it possible to lower my pH without additives? My current pH is about 7.5 as reported by an API kit. Though I don't understand why, the forced flow dynamics of my tank push pH towards alkalinity.

I have no reason to disbelieve him, but still don't understand why he thinks that this "full cycle" is so important. What is the benefit of lowering nitrates to near zero unless you have an overstocked tank with consistently high nitrates despite regular water changes. Even if had near zero nitrates I would still feel it necessary to maintain my water changes in order to replenish minerals and prevent the build up of other potential toxins.

What I got from the content was that it's possible to lower nitrates enough to decrease the need for large frequent water changes. This would be fine by me. In fact just mentioning the possibility got my tank budget raised.

The blocks/ sausages are not all exactly the same size and do not stack particularly well in small filters.

He mentioned that it's possible to break down the sausage media by hand to better suit smaller application's.

 

I'm a born hobbyist RC, and I have a deep admiration for honest entrepreneurs. Pong Guru was obvious about his personal considerations from the start, which I admire as well. The fact that his products are SOTA, and verified as such, is the only factor that's important to me. I mentioned my status as a flaming hobbyist, so you'll hopefully understand my mindset to the highest degree possible. My intent in telling you this is to ease tensions and make it easier for you and I to converse and exchange relevant data, if need be.

My intention is to create a nitrate reactor out of one of my filters. Once I absorb what I can from PG's content and Pfrozen's excellent post, it should be easier than I had anticipated. I'll start this journey with a question: Is it possible to lower my pH without additives? My current pH is about 7.5 as reported by an API kit. Though I don't understand why, the forced flow dynamics of my tank push pH towards alkalinity.

Very easily. Try skipping some water changes with a "full cycle" filter and you will find yourself running out of KH due to mineral depletion, this is directly connected to your pH. You could achieve the same running an extremely planted tank that takes in a good portion of nitrate as well.

In the FWIW department: the turnover rate recommended by many, usually between 4-10 would typically help keep a tank from developing dead zones caused by eddy currents etc. These are very common with hardscape intensive, or leafy tanks. In a hard scape or artificial plant tank there will be nothing helping oxygenation in the water that is sitting stagnant. One could use a DO meter and/or dip tubes and basic testing to find a variety of parameter variance in different locations throughout a stagnant tank.

In stagnant lakes in nature, there is a thermocline layer, usually accompanied by a low oxygenation zone just deeper due to the limits of thermal convection induced turbulence. This would go against common thought process of most aquarist as it's commonly stressed that cooler water has more oxygen, but this is no longer true if there is not adequate gas exchange and circulation.

Don't get this all mixed up, I'm an expert of very little and DIY stuff is my main wheelhouse, especially the fluid dynamics portion. The example of the lake is one I learned from some volunteers at a hatchery, I was able to witness it kokanee fishing and then invested allot of time into researching the theory involved.

One thing I will put out here, I do appreciate the videos cory and pond guru put out but... Cory is very profit oriented, half of his streams are focused on this exact thing. I don't think I need to say too much more on it but we could get allot farther scientifically quoting articles that are peer reviewed and found on NCBI or several universities biotech pages than affiliated/sponsored product placement videos on youtube.

Very interesting thread, let's stay non-combative if we could.

 

I have no reason to disbelieve him, but still don't understand why he thinks that this "full cycle" is so important. What is the benefit of lowering nitrates to near zero unless you have an overstocked tank with consistently high nitrates despite regular water changes. Even if had near zero nitrates I would still feel it necessary to maintain my water changes in order to replenish minerals and prevent the build up of other potential toxins.

It’s quite important for me because the nitrates out of my tap measure 50PPM at least so doing a large water change would do nothing for me, the tried and tested method simply wouldn’t work for my water supply without changing to an RO supply.

Ive used biohome for about a year now, and it does work, it obviously requires a bit of cost and set up to do it right, like having the minimum kilogram of media per 100 litres of water, but the level of nitrates is consistently around the 10PPM level, despite me putting 50PPM water into the aquarium through partial water changes.

The only other product that I’ve tried to comes close to being as effective at consistently processing nitrates is the dreaded tetra Easy Balance that seems to have a terrible reputation on forums, but again it does work pretty well and pretty much does what it says on the label, despite people saying it’s nothing but a snake oil.

I do think many fish keepers seem to be very protective of the methods that work very well for them and what are the traditional accepted norms of the hobby, and like to dismiss anything new or different out of hand. The filter flow rates are a good example of this in my opinion.

 

I've had Brightwater running for about 6-months, but I can't say it's been under optimal conditions as PG describes them at least. Once I adapt my kit to have an anaerobic component, I expect naturally lower nitrates which in turn decreases frequency and volume of water changes, which would be just fine by me. Though it would be nice to be able to negate water changes entirely, I don't expect it anytime soon. I mentioned Brightwater above (which I've run for a while) because it, like biohome U, has a denser more isolated core which is apparently ideal for aerobic/anaerobic bacteria to colonize.

Also, I think there's a bit of confusion between filter flow and water flow as it exists in the tank itself. While turning a tank over 10x in an hour is fine, it doesn't necessarily translate to 0 dead spots or no thermal anomalies. Remember guys, another way to say "theory" is "guess." A theory isn't fact until it's proven and adopted safely.

 

I have no reason to disbelieve him, but still don't understand why he thinks that this "full cycle" is so important.

It may be possible that he's playing to a different audience when he's hawking "full cycle." I have only my memory to draw on when I say this but I recall that some adhere to a much longer water change cycle than the majority here think is feasible. To such an audience having a filter acting as a nitrate furnace makes sense a lot of sense.

 

It may be possible that he's playing to a different audience when he's hawking "full cycle." I have only my memory to draw on when I say this but I recall that some adhere to a much longer water change cycle than the majority here think is feasible. To such an audience having a filter acting as a nitrate furnace makes sense a lot of sense.

Perhaps. Personally I think nitrate management is just one of several reasons for changing water. What I thought were more interesting were his negative comments on Prime and Purigen based on his customer’s experiences. He couldn’t really explain it though. Although he didn’t name them I assume they were the products he was referring to.

 

Without much prompting I accepted long ago that both fresh and saltwater contain substances that support life. Since my current configuration (no aristones) doesn't precipitate minerals from my water it's obvious that those substances need to be refreshed and replenished from time to time. Not being a chemist, meatball or otherwise, water changes will continue to be the best all-around way to keep my fish healthy.

Now, since I think we can all agree that less nitrates is clearly better, I'll proceed to look for a way to minimize the volume and frequency of WC's. I hope you can find a manufacturer that doesn't down toot the competition from time-to-time and produces a product that you want to use, Glenn.

 

Perhaps. Personally I think nitrate management is just one of several reasons for changing water. What I thought were more interesting were his negative comments on Prime and Purigen based on his customer’s experiences. He couldn’t really explain it though. Although he didn’t name them I assume they were the products he was referring to.

I think the theory of the potential issue with using prime when you simply want to dechlorinate the water is that ‘locking up’ or ‘binding’ ammonia and nitrite is that it starves bacteria of its food source when establishing a cycle. I have no idea if there’s any merit to that at all, but I’m sure I read something very similar also in the Q and A with Tetra on here regarding tetra safe start, obviously a cynic could say that tetra have an obvious dog in the fight in regards to selling their own water conditioners, but as far as I know the pond guru does not sell or promote any water conditioners on his website, it simply recommends using anything that simply removes chlorine from tap water, rather then something that claims to do anything more then that.

like I say, the biohome ultimate works well for me with the ridiculously high nitrates in my tap water, I like the product. I tried Matrix and didn’t achieve the same results, although I only used a fraction of the amount of Matrix as I have biohome, as Seachem really don’t offer any advice on how much Matrix is needed to grow anaerobic bacteria to process nitrate, had I used the same amount maybe I’d have gotten different results.

One other thing I’ll say on the subject of the biohome is that the Pond Guru or Richard is not some ruthless salesman trying to sell a miracle product. If you have any questions about the product drop him a mail or call him up, that’s what I did and found him pretty honest about the limitations of the product and how it’s not always needed in circumstances such as heavily planted tanks that deal with nitrates naturally. There was no claim of not having to make water changes or anything radical like that, rather then making huge water changes of 50% weekly or whatever I simply remove and replace a much smaller percentage, as much as it takes to have a good vacuum of the and clean of the substrate is enough for me now. While I think it’s healthy to question everything and test everything ourselves, I don’t see why people like Richard the pond guru or even the likes of Cory from Aquarium co-op should be trusted any less then something printed on say a Seachem/Ehiem/Fluval product or website, pretty much everyone has a financial interest in selling their products, doesn’t automatically mean people are not being truthful.

 

I do not know specifically what is in Seachem Prime, but most people who have used it seem to think that it makes the ammonia less harmful to the fish without removing it totally from the system. Thus, it is supposed to be useful during a fish-in cycle. The fish are protected and the beneficial bacteria still have access to the ammonia as a source of nutrition. Because of this, when you test for ammonia in the tank, the test will show ammonia present even though it may not be toxic to the fish.

I have heard reports that some other ammonia removal products can be harmful to the beneficial bacteria during the cycle process. For example, using zeolite will absorb ammonia making it unavailable to beneficial bacteria growing in other parts of the system. I suspect beneficial bacteria will grow on the surface of the zeolite just like other surfaces, but when the zeolite is removed for disposal or regeneration, the bacteria will be lost.

 

I don’t see why people like Richard the pond guru or even the likes of Cory from Aquarium co-op should be trusted any less then something printed on say a Seachem/Ehiem/Fluval product or website, pretty much everyone has a financial interest in selling their products, doesn’t automatically mean people are not being truthful.

Wow! I was expecting rapid, detailed responses to the above. I too thought it was normal to hawk a product that you yourself own and something to be expected. Since some folks see personal research as beneath them, here's a negative review of Biohome U:

Don't forget to review the comment log, if you're so inclined.

 

I’ve noticed when reading articles and care sheets about different types of fish, and also on Internet forums people often mention minimum times you should turn over the tank volume, often ridiculously high ratios like 10 times the tank volume are quoted, to me it seems without any workings or science to back this up.

While I agree with the general consensus that more filtration is never a bad thing (unless you have fish that struggle to swim in a lot of movement) but I’m interested as to why a certain flow rate would be needed in an aquarium? If your filter has enough media to handle the bio load, and you have sufficient aeration/movement, I struggle to see why anyone would strive to achieve 300 gallons of flow an hour in say a 30 gallon tank, or even 5 times the volume. Seems a bit like the inch per gallon rule to me, something people quote without really knowing too much about it. I can see why in heavily planted tanks it’s more important, but African cichlid keepers seem to think it’s very important and they don’t have plants.

I’d like to know people’s thoughts and theories on this, as it’s something I completely overlook, after all my mechanical filtration, bio media and pipes, my canister filter only has an actual output of about 40% of the manufactures quoted flow, which is about 2.5 times the tank volume, but as far as I can tell it still easily handles (no ammonia or nitrite) the bio load in quite heavily stocked tank.

I have kept planted tanks for over 17 years and a very high flow is never really necessary or wanted. One thing you don’t want are dead zones within your tank. So that is why it’s very important to understand how your equipment works and find the best place to put your intake and output if you have a canister filter. With an HOB (hang on back) you are limited to this factor but there is thing you can do to help the flow in your tank. As for the GPH flow of our filters most people truly don’t understand the physics behind them. The amount and type of media you run in your filters has an immediate effect on your filters’ flow rate; for you are creating resistance to flow with the media we are placing. Combined this with head pressure your pump / motor has to work against and the parameters quoted on the box of our filters is drastically changed. I have never kept African Cichlids so I can’t speak to the why in an intelligent or informed way because I have never had experience with those types of tanks. But I do understand that the one major factor those aquarist are always battling is removed of mass dissolved organics within the water column based on the fact how messy eaters Cichlids are by nature. I kept Oscars and Jacks when I got started in the hobby. Since then, I have concentrated my time and energy in the beauty of planted community tanks.
In a planted tank you want a nice gentle current so nutrients are disperse evenly throughout your tank and so that any detritus left on the surface of our substrate is pushed or moved towards the intake tubes of our filters. Strong water current also can disrupt the photosynthesis process and that another reason you don’t want very strong currents.

 

I think the theory of the potential issue with using prime when you simply want to dechlorinate the water is that ‘locking up’ or ‘binding’ ammonia and nitrite is that it starves bacteria of its food source when establishing a cycle.

I have no issue with anything that he said I just said that it was interesting for that reason. Given that we are led to believe that the binding process does not affect the cycling process. Quote from Seachem:

"Prime® works by removing chlorine from the water and then binds with ammonia until it can be consumed by your biological filtration (chloramine minus chlorine = ammonia). The bond is not reversible and ammonia is still available for your bacteria to consume. Prime will not halt your cycling process".

So it's interesting that some of his customers report that Prime affects their ability to achieve the so called 'full cycle'.

 

Speaking as a happy fish only keeper, I've yet to hear or read anyone bragging about having the sort of head pressure needed to pump through variable mat density can filter, and return it to a tank in such a way that doesn't modify their fish and scaping into water-borne projectiles. I did see a beautiful 300g marine (on a old aquarium show) with an equally sized multi-tiered sump, in the basement. It was either a fabulous DIY job or a big $ custom setup. Not a kit Average Joe is likely to have.

Backblast, since I don't do plants this may be a silly question: Do plants have a boundary layer that needs to be agitated for best health?

 

Remember guys, another way to say "theory" is "guess."

Entertaining, but off base with me. Stratification in bodies of water is a fact. Even when a thing is a fact there is a theory of operation behind it.

The hypolimnion region of a stratified lake is a different density; liquids of different densities do not mix as easily as liquid of the same density. The reason I said "theory" instead of typing out a book about this is because there is simply too much to explain individually, factually, to not be thread jacking this from the OP. It was just an extreme example of why dead zones are bad in a tank. And no, I don't think any of us have a tank deep enough to stratify, but circulation affects several parameters differently in various locations throughout a tank.

Spoiler: More ranting about theories vs facts

Take for instance the device you are reading this on, if you were to tell the engineers that "electronics theory" wasn't enough to come up with a fact, I think you would find yourself wanting for any electronics device. Theory of stoichiometry, cars must not run if that theory doesn't contribute to combustion theory, which, well I guess it's just a guess, couldn't be a fact as well that was based on theory

Find a white paper in NCBI or another peer reviewed science outlet, and let me know how many theories are guesses.

I can't contribute much to the 'which bio-media is better" conversation this has turned into. The last time this conversation came up I watched several members get so defensive of the overpriced purchases they wanted to say worked due to personal confirmation bias they ended up banned. The unfortunate part is that they were not nearly as dismissive and condensing as the replies in parts of this thread; it was fun with them as they would find as many white papers as possible and bring out fun facts like the surface are per volume of their medias of choice, flow rates expressed in actual measurement units, and other things I haven't seen much here as this thread went from turnover and flow rate (which is a genuinely interesting subject) to biohome best home, which is also interesting but not where this thread was headed.

 

Entertaining, but off base with me. Even when a thing is a fact there is a theory of operation behind it.

"Entertaining" in what way? I don't remember addressing you directly or asking for a critique of a simple AND factual statement.

Stratification in bodies of water is a fact.

Not in the case of an average aquarium, it isn't. Now if you want to opine about military submarine evasion tactics there's something to converse about. Otherwise, it would seem appropriate to stay within the threads title.

 

Otherwise, it would seem appropriate to stay within the threads title.

"Tank turnover theories"

You call those guesses, but they definitely aren't biohome.

 

"Tank turnover theories"

You call those guesses, but they definitely aren't biohome.

I'll just disregard this incomprehensible post, from a person who admits to knowing very little about sintered glass variable density biological media or how it can easily fit under the thread topic. It's too bad that I stumbled on a trigger phrase for you, really.

 

Speaking as a happy fish only keeper, I've yet to hear or read anyone bragging about having the sort of head pressure needed to pump through variable mat density can filter, and return it to a tank in such a way that doesn't modify their fish and scaping into water-borne projectiles. I did see a beautiful 300g marine (on a old aquarium show) with an equally sized multi-tiered sump, in the basement. It was either a fabulous DIY job or a big $ custom setup. Not a kit Average Joe is likely to have.

Backblast, since I don't do plants this may be a silly question: Do plants have a boundary layer that needs to be agitated for best health?

The plants ability to correctly carry out photosynthesis can be affected by very fast current. Plants absorb nutrients in two basic ways: a) through their roots and b) through their leaves. Therefore, in a planted tank you want a gentle current throughout the tank so that nutrients are equally dispersed within the water column and the plants can assimilate these nutrients. The plants which mainly take in nutrients through their roots are thus not greatly affected but plants which are not heavy root feeders will. A good example would be: an Amazon sword ( heavy root feeder) vs. an Anubias Nana ( these plants are not planted into the substrate ) and therefore, their rhizomes are above the substrate and most of their nutrients are absorbed through their leaves.

 

The plants ability to correctly carry out photosynthesis can be affected by very fast current. Plants absorb nutrients in two basic ways: a) through their roots and b) through their leaves. Therefore, in a planted tank you want a gentle current throughout the tank so that nutrients are equally dispersed within the water column and the plants can assimilate these nutrients. The plants which mainly take in nutrients through their roots are thus not greatly affected but plants which are not heavy root feeders will. A good example would be: an Amazon sword ( heavy root feeder) vs. an Anubias Nana ( these plants are not planted into the substrate ) and therefore, their rhizomes are above the substrate and most of their nutrients are absorbed through their leaves.

We're back in the realm of informative content. Thanks for reminding me why planting my tank seems so scary, BB72.

 

We're back in the realm of informative content. Thanks for reminding me why planting my tank seems so scary, BB72.

I wouldn’t say scary but there is several factors you have to take in consideration. The main thing when deciding to go with a planted tank is choosing what TYPE of plants you want. What I mean by this is fast growing vs. slow growing plants. And the reason for this fast growing plants will require more nutrients, carbon dioxide fertilization and the number one factor in the triangle of balance very high lighting. After all from the three factors within this triangle (Nutrients, Carbon Dioxide, and Lights) LIGHTS is the most important factor for it drives the other two. And thus, once you make the decision of fast vs. slow then you can plan accordingly and not have any nasty surprises later down the road with them. Now this said, plants do have A LOT OF POSITIVES vs. NEGATIVES. Plants after all are nature’s filter and nothing within the hobby will beat them at this. Planted tanks can be a lot of fun no doubt and also a lot of work. But once you get the basics down they can be extremely rewarding. I started in the hobby back in 1996 with Oscars and Jack Dempsey’s later on during the year I got invited to a fish show and that’s when I saw a densely planted tank for the fist time. It was love at first site. I read a lot and did my research on what type of set up I wanted and it wasn’t until 1999 when I had my first planted tank; I’ve been keeping planted tanks ever since and last year was my first time when I ventured into a dirted tank. So it’s been a new learning curve but I love it.

 

My thought and theories... Probably wrong btw.... But in use currently

Water changes to some degree are obviously nessesary. For some of us me included smaller water changes lead to less swings in ph or reduced need for purchased water.
Some of us me included have never needed to use water conditioner (private untreated spring or well) but don't always have perfectly matched water either. These are absolutely times when a smaller water change can be better.
If you know your going to be in this situation upsize your filter, it will make life easier.

So that said

I use an alternative filtering system on my main tank currently filled to 100 ish gallons and my flow rate is slow ... I also run a really small homemade sponge filter to keep it primed for emergency use elsewhere. Maybe it's not that small I don't know it's built in a 4" diameter 4 inch tall cylandar vase

But...The main tank is understocked. The entire filtering system made of three separate components holds slightly more water (200 gallons) than the stocked fish tank portion of the system. The system is cold and has way more oxygen holding capability than most tropical tanks. There are air stones. The system also has more than 25 square feet of water surface area to allow for tons of gas exchange. The system has a truly ridiculous amount of space dedicated to bacterial colonization. It has various components for mechanical and biological filtration. There has been no need to add charcoal or use any chemical filtering additive.
Guess what? It works. Actually we overdid it and it works too well.


But this isn't the least bit practical for most people. So even though everything I put together works it's still not suggested. Not even by me, unless there's a really good reason to avoid the more obvious 10x filtering recommendation.

So in this hobby there are lots of "rules" and they exist to make it easy for newcomers to jump in and have immediate success. Success with fish can be really hard if you don't follow any of the rules. Or fairly straightforward if you follow at least some or most of them.


IMO the reason for the high water volumn turnover is to guarantee appropriate oxygen levels. This was already discussed in depth above.

This wouldn't really be that important except that in building pretty fish communities we often compromise on fish temperature preferences, Especially in the beginning.

When you put a fish in water even slightly warmer than it wants to be in it can easily become oxygen deprived, as the warm water naturally holds less oxygen. To compensate for this eventuality it is often recommended to way overdo the filter.

It also eases up the maintenance burden and compensates for the other really common issue of overstocked first tanks. That said it's not perfect and in some situations, stocking scenarios, and tanks, low flow will absolutely work better.

Like anything proceed with caution do the research and you can make lots of alternative setups work for fish. But if you want quick success with way less effort follow the rules and advice commonly referred to and you will do ok. That's the whole point of these rules. They make it easy.

And honestly if the wonderful man that owned the LFS where I grew up hadn't so rudely insisted I follow all the rules on my first tank. (He even refused to sell me what he called "the wrong" fish, Imagine.) I wouldn't be nearly as successful breaking those same rules now, in fact I probably would not even have fish.

Those first successes were important. They kept me in it even when tanks crashed and fish died because I had a method and formula that I knew worked. I want everyone to feel that way. I want everyone to get a taste of success in this hobby even if only for a minute.

So even though I know my filter won't turn over my water 10x every hour, I still recommend people buy the best filter they can afford and I don't tend to argue with the 10x an hour rule. It's there to help anyone that could still benefit from easy to follow rules have success and there's nothing wrong with that.

 

I wouldn’t say scary but there is several factors you have to take in consideration.

I'm sorry that I didn't respond sooner, BB. I've been dealing with a very painful malady that would taint my view of any hostile post that was pointed in my direction. I'm hoping that I'm coming out of it so Ill try to proceed as before.

The word "scary" still applies in my situation because redoing my tank to nurture a completely different lifeform, would require the sort of energy I simply don't have. I'd much rather indulge in another hobby that the wife and I have which is raising/training rescue pit-pulls to be the dog-faced, overly-pampared couch-potatoes they can quicky become. Having said this, I want you to know how much I appreciate your knowledge and expertise in planted tanks. Perhaps when I get my new acrylic tank we'll start it planted with loads of neon tetras.

View attachment 784033

 

Wow! I was expecting rapid, detailed responses to the above. I too thought it was normal to hawk a product that you yourself own and something to be expected. Since some folks see personal research as beneath them, here's a negative review of Biohome U:

Don't forget to review the comment log, if you're so inclined.

I bought two pounds of the Biohome Ultimate and it’s been seven months and my nitrates are at the same level they were Seven months ago. I took that stuff out of my canister filter and bought Fluval’s Clearmax and not only did my nitrates came down but also my phosphate levels. The Fluval product was way cheaper and I Saw a significant change which I detected while monitoring my water parameters. So I wouldn’t recommend the Biohome to anyone it’s just a money scam.

 

I bought two pounds of the Biohome Ultimate and it’s been seven months and my nitrates are at the same level they were Seven months ago. I took that stuff out of my canister filter and bought Fluval’s Clearmax and not only did my nitrates came down but also my phosphate levels. The Fluval product was way cheaper and I Saw a significant change which I detected while monitoring my water parameters. So I wouldn’t recommend the Biohome to anyone it’s just a money scam.

Biohome is biological media and Clearmax is chemical media. I would expect chemical media to provide more effective and immediate results in removing the targeted nutrients since that is what it is expressly designed for. Biohome is designed to maximise bacterial populations. It claims to be able to accommodate nitrate reducing anaerobic bacteria in the longer term (although your own experience which was worth sharing suggests otherwise) but it’s a very different process to chemical adsorption. Nevertheless I’m glad you found a product that meets your needs and works well for you.

 

Biohome is biological media and Clearmax is chemical media. I would expect chemical media to provide more effective and immediate results in removing the targeted nutrients since that is what it is expressly designed for. Biohome is designed to maximise bacterial populations. It claims to be able to accommodate nitrate reducing anaerobic bacteria in the longer term (although your own experience which was worth sharing suggests otherwise) but it’s a very different process to chemical adsorption. Nevertheless I’m glad you found a product that meets your needs and works well for you.

I agree with your observation. I was not trying to say Biohome is a chemical filtration media. What I was trying to share is that I had a completely established filter in which Inadded Biohome and it’s been seven months. More than enough time for anaerobic bacteria to colonize the media. But my nitrates did not go down at all. My bio load did not change, nor the amount of food being feed to the fish and above all neither did my maintenance schedule. I should have at the very least seen a small change but at least in my tank I saw no CHANGE IN NITRATES. That’s why I made the comment / observation on the Biohome. I been at this for a hot minute (20+) years so it’s not like I’m a rookie and don’t know what I’m doing.

 

I agree with your observation. I was not trying to say Biohome is a chemical filtration media. What I was trying to share is that I had a completely established filter in which Inadded Biohome and it’s been seven months. More than enough time for anaerobic bacteria to colonize the media. But my nitrates did not go down at all. My bio load did not change, nor the amount of food being feed to the fish and above all neither did my maintenance schedule. I should have at the very least seen a small change but at least in my tank I saw no CHANGE IN NITRATES. That’s why I made the comment / observation on the Biohome. I been at this for a hot minute (20+) years so it’s not like I’m a rookie and don’t know what I’m doing.

Noted. Perhaps I incorrectly read it as a direct results comparison between chemical & biological media.

 

Biohome is biological media and Clearmax is chemical media. I would expect chemical media to provide more effective and immediate results in removing the targeted nutrients since that is what it is expressly designed for. Biohome is designed to maximise bacterial populations. It claims to be able to accommodate nitrate reducing anaerobic bacteria in the longer term (although your own experience which was worth sharing suggests otherwise) but it’s a very different process to chemical adsorption. Nevertheless I’m glad you found a product that meets your needs and works well for you.

Moreover, not adhering to PG's ideas for maximizing Biohome functionality isn't giving the media itself a fair test.
He mentioned in the video I posted that Biohome needs to be protected by a multi-tiered foam structure easily added by popping for a filter-booster (separate prefilter). This step, according to him, is dual purpose: It keeps as much debris as possible from the tiny holes the media is laced with. Second it slows flow a bit, giving the denser core a better chance to rapidly populate and grow.

To be perfectly clear here, I'm not married to the idea of using Biohome. I simply see it as potential remedy\amelioration for having to schlep around 40gx8-pounds every week. If it fails a proper test I can easily go back to what I was doing before, which works fine, and see it as a lesson learned.

 

I bought two pounds of the Biohome Ultimate and it’s been seven months and my nitrates are at the same level they were Seven months ago. I took that stuff out of my canister filter and bought Fluval’s Clearmax and not only did my nitrates came down but also my phosphate levels. The Fluval product was way cheaper and I Saw a significant change which I detected while monitoring my water parameters. So I wouldn’t recommend the Biohome to anyone it’s just a money scam.

What is the size of your tank? 2 pounds of biohome will only reduce nitrates in a tank of about 24 gallons or 90 litres, anything bigger you might aswell use something way cheaper with if you only have space for that amount of media in your filter set up. That seems to be the major drawback with this media, for say a 50 gallon tank you’d need at least 4 pounds of the stuff for it make a difference to nitrates, which would be expensive, but to be fair they’re very clear and honest about the amount they recommend. For me it’s was worthwhile and does do what it claims.

 

What is the size of your tank? 2 pounds of biohome will only reduce nitrates in a tank of about 24 gallons or 90 litres, anything bigger you might aswell use something way cheaper with if you only have space for that amount of media in your filter set up. That seems to be the major drawback with this media, for say a 50 gallon tank you’d need at least 4 pounds of the stuff for it make a difference to nitrates, which would be expensive, but to be fair they’re very clear and honest about the amount they recommend. For me it’s was worthwhile and does do what it claims.

 

I’ve noticed when reading articles and care sheets about different types of fish, and also on Internet forums people often mention minimum times you should turn over the tank volume, often ridiculously high ratios like 10 times the tank volume are quoted, to me it seems without any workings or science to back this up.

While I agree with the general consensus that more filtration is never a bad thing (unless you have fish that struggle to swim in a lot of movement) but I’m interested as to why a certain flow rate would be needed in an aquarium? If your filter has enough media to handle the bio load, and you have sufficient aeration/movement, I struggle to see why anyone would strive to achieve 300 gallons of flow an hour in say a 30 gallon tank, or even 5 times the volume. Seems a bit like the inch per gallon rule to me, something people quote without really knowing too much about it. I can see why in heavily planted tanks it’s more important, but African cichlid keepers seem to think it’s very important and they don’t have plants.

I’d like to know people’s thoughts and theories on this, as it’s something I completely overlook, after all my mechanical filtration, bio media and pipes, my canister filter only has an actual output of about 40% of the manufactures quoted flow, which is about 2.5 times the tank volume, but as far as I can tell it still easily handles (no ammonia or nitrite) the bio load in quite heavily stocked tank.

I too bought into this when I first started fish keeping but ironically I like river fish so they like the high flow, over time and tank conditions with x amount of water turning over I realized it's not nessesarily the turn over rate that helps the fish/water/evaporation...all that stuff.
I've determined it's how long ,slow and consistent you can keep the water moving over the filter media.
I have a 6 ft long tank w/ a 7 ft long filter made from gutter channel at home depot.
I tried to create a water column just for filter media
And as of a year later it thumps.

 

I too bought into this when I first started fish keeping but ironically I like river fish so they like the high flow, over time and tank conditions with x amount of water turning over I realized it's not nessesarily the turn over rate that helps the fish/water/evaporation...all that stuff.
I've determined it's how long ,slow and consistent you can keep the water moving over the filter media.
I have a 6 ft long tank w/ a 7 ft long filter made from gutter channel at home depot.
I tried to create a water column just for filter media
And as of a year later it thumps.

While I agree with the essence of what you're saying here it's important to separate filter flow (filter exhaust throughput) from in-tank flow. They can be very different depending on how filter exhaust is directed and it's velocity. The idea of in-tank flow is consistently different based on its origin and complexity. This is something I have direct and growing knowledge of.

Being that I've mentioned this at least once, without discernable challenge OR acknowledgment indicates to me that the factual nature of what I'm saying is likely being dismissed/ignored. This isn't about my "feelings", not at all, but only a wish that this interesting and important topic be seen in a more factual manner.

In closing I'd like to mention something I learned recently. Eheim is the only manufacturer that publishers their estimate of true filter flow, taking into account the media loaded in their filter offerings. Goodnight all.

Special mention to Patman0519 for some intersting DIY filter work.

 

While I agree with the essence of what you're saying here it's important to separate filter flow (filter exhaust throughput) from in-tank flow. They can be very different depending on how filter exhaust is directed and it's velocity. The idea of in-tank flow is consistently different based on its origin and complexity. This is something I have direct and growing knowledge of.

Being that I've mentioned this at least once, without discernable challenge OR acknowledgment indicates to me that the factual nature of what I'm saying is likely being dismissed/ignored. This isn't about my "feelings", not at all, but only a wish that this interesting and important topic be seen in a more factual manner.

In closing I'd like to mention something I learned recently. Eheim is the only manufacturer that publishers their estimate of true filter flow, taking into account the media loaded in their filter offerings. Goodnight all.

Special mention to Patman0519 for some intersting DIY filter work.

I agree with you, the turnover rate of my tank if I had a guess is around 80 to 90 gallons an hour.
For in tank I have 2 wave makers a 900 gph and 120. And 2 power heads 400gph

 

I agree with you, the turnover rate of my tank if I had a guess is around 80 to 90 gallons an hour.
For in tank I have 2 wave makers a 900 gph and 120. And 2 power heads 400gph

If I was going to guess I'd say that filter turnover across both units is about is about 240GPH for me. Less restrictive flow was something I was shooting for when I started buying large, geometrically-identical media for the biological components of both filters. The "anaerobic" thing was/is just icing.

My wavemaker is a true gem. It supports 80-800 gallon tanks, burns 5 to 52 watts and pushes up to 5280GPH. We've set it to run 3-cycles\day. Straight laminar flow -pulsed laminar flow (brushes the substrate of lighter particles and suspends them in the column) - powered off at night so my fish can rest. The setup works so well that my two youngest fish go looking for the missing flow at night.

It also gives 100% surface agitation without the mineral crust I got used to from two airstones, at 10-30% power.

 

The best evidence for those of us that use 10X plus in GPH filtration is the clarity of the water.

 

The next time I visit one of my local club members fish rooms I will with his permission take a snapshot of some of his tanks. He is running a central air system and could run a lot more filters ( sponge filters) if he wanted. One tank that comes to mind is around 40 gallons with what I would call a heavy stocking including the fry from a special cichlid . It has one medium sponge filter and that’s all I think. Many of his tanks are small but the half dozen or so large tanks all seem to be low on the numbers of filters ( by my standards) . Of course this guy is a long time member of the club who is always bringing juvenile fish to auction .

I encourage anyone to join a club and visit other peoples set up’s. Even if it’s just on zoom ( virtually) at the moment.

 

I encourage anyone to join a club and visit other peoples set up’s

This is great advice. Especially people with significantly different set ups. I'm the only real nano guy in my local club and it's crazy visiting the monsters keepers and their 400+ gallon living room tanks with garage tank back ups just as big or bigger. I haven't run across anyone locally running much less filtration than me though, allot of huge canisters and sumps. The most fascinating local guy breeds a bunch of Tanganyika cichlids in racks of 75 gallon tanks. He's running dual AC110s on each with no air systems. He gets his anubias to grow vertical like palm trees, truly fun to visit with.

 

The best evidence for those of us that use 10X plus in GPH filtration is the clarity of the water.

Very nice, I’m still confused though about the claims of 10X plus in GPH. I’ve tried many different filters, and I’ve never tested a canister filter when hoses are connected and filled with media that has an actual output above 50% of what it says on the box. So if the manufacturer claims the pump has a flow rate of 1000 GPH, it’s much more like 500 GPH when set up on a tank, or if they say 500 GPH it’s more like 250 GPH.

So unless I’ve just had bad luck with canister filters, say if I had a 50G tank, to realistically turn the tank over 10x per hour I’d need 2 FX6 filters (563 GPH manufacturers claim) to make sure I turned the tank over 10 times. That still seems obscene to me on a 50-60 gallon tank, unless the tank was stupidly over stocked.

 

As long as a manufacturer doesn't deliver the science, be very, very skeptical. The best test is simply to measure water parameters. And in case of a planted tank; the plants will tell you if they are doing fine or if they are struggling.

A manufacturer of filters no doubt sees his equipment as the center of the universe. In my planted tanks, I see it primarily as a means to move water inside the tank. So I judge filters purely on this. Bacteria are everywhere; my substrates have plenty. So the importance of the filter depends heavily on where you find yourself on the continuum of "tank cleaning" versus "let nature take care of it". The latter can even do without a filter.

 

For the sake of clarity *snicker* I will restate what I have said over the years on this forum. My passion in life is photography followed very closely by tropical fish. The health and well-being of the fish always comes first. To achieve the technical quality of the fish photos I post (the artistic value is subjective) the water must (as well as the glass) be clean as possible.

I have also said over the years that there are far too many variables each one of us has to deal with across the world to speak in absolutes. Sadly there are those that come to this forum just to pick fights. Gotta love that ignore option