How much bio filter is too much?

[Pinkey]

Hello,

The amount of bacteria that live on the surface of the filter media are limited to their food supply (generically, broken down fish waste).

It is useful to have enough real estate to host a colony large enough to process the entire system's waste.

It wouldn't make sense to have 10 cubic feet of bio balls on a tank with three 4" goldfish.

Has this been addressed in the forums already? Aquaponics people measure systems with the ratio of food added at the top of the food chain (pelets) to plants. (A 10k gallon system can handle X fish eating X kg of food per day when paired with X meters squared of plants.) Is there a similar chart for us tiny-scale home aquarium folks? I looked for this in the forums but my search skillz are not that mad.

In my specific case I am looking for how many cubic feet of bio balls are needed to house bacteria for 3 oscars, 2 pictus, 1 jack dempsy, and 1 parrot fish. I have plenty of space in the aquarium stand and the DIY sump for far more than enough media but would like to use extra space for other experiments rather than unsaturated bio balls.

Thank you, in advance.

 

[Glabe]

I haven't heard of any ratios, and Google didn't help me find one just now, either. Is there an overflow with room for sponge filters or DIY filtration to help save space down under?

Btw, what's your tank setup?

 

[stingray4540]

I think the ratios you refer to defer from the home aquarium in a couple of ways.

From what I've ascertained from my research, those ratios are due to the balance needed to run an aquaponics system. They are relying entirely on fish to feed the plants, and the plants to consume nitrates, as they don't practice water changes, or try to grow nitrate bacteria.

Too many fish and the plants can't keep up with the nitrates, too few fish and the plants don't get the optimal amount of nutrients.

I think you will find that with the right bio media you don't need that much, but of course it won't hurt to have too much. Remember, bacteria is everywhere, on your decorations, in the substrate, in the sponges and bio media, etc.

If your ammonia and nitrite readings are 0, you probably have enough filter media...
If you have spiked or fluctuations, you probably need more.

I don't know of any hard fast rules of how much media you need for x amount of fish.
I just generally always pick a filter rated for my tank, and doubled it, but that is only because that has been engrained in me from spending too much time on forums... And I think that number is based on mechanical filtration more than biological filtration.
But I digress.

I would be interested if anyone had any general rules for amount of filter media per amount of fish, but I suspect there are to many veritable a to be very precise.

 

[ZorroNet]

I agree... Precision is hard with so many factors. Is it planted? How much decoration is in the tank? How deep is the substrate? What kind of substrate? What is the water flow like? All of these questions are valid in determining how much filtration is needed... Dare I say, "if any". People freak out about ratings and numbers on equipment, but equipment is not the only factor.

Water can be stabilized with no filtration at all, but not with ease. Call me a planted tank nut, but I think plants change everything! I am so glad I have planted tanks, and I don't have to deal with the same problems others do with water quality because the plants do so much of the work for me!

I know cichlids are rough on plants, but what about a planted sump? I have been thinking about this a lot lately. Call it aquatic plant aquaponics, but I think it might just work! The idea is to plant the sump tank and the fish will reside in the main tank benefitting from the water cleaning power of the plants without ever seeing them (and destroying them). I don't have a tank I can do this with, or I would do it myself.

Sent from my iPhone using MonsterAquariaNetwork app

 

[excuzzzeme]

There is no hard and fast rule that can be applied globally. There really isn't such a thing as too much biomedia. You will have 'X' amount due to limiting factors. Limits are based on the # of fish, the size, amount of waste generated, amount and type of plants and the amount of water available.


--- Aerobic and anaerobic bacteria are pretty much self-limiting based on how much nutrients are in the water column and how much water and food is available to them. I personally have never heard of anyone being able to maintain plants in a tank of Oscars. That doesn't mean it can't be done. You will need to find a way to anchor the plants so they can't be uprooted and moved.

--- Yes, putting plants in the sump is very common (I did that too) and doing so just makes the sump a refugium. That would work to actually filter the water and cut down on the need for massive amounts of biomedia. You would still propagate your bacteria in both tanks and the plants doing a percentage of the uptake. Make up a log book and keep record of the number of plants and type. Yes, there are plants that are considered nitrate hogs and deep rooted plants would not benefit except thru root feeding (Amazon Sword type). You will need to decide if you want water column feeders (ideally to do the uptake). Next you will need adequate lighting for the plants. The main display tank doesn't need much in the way of lighting except for personal viewing tastes. Once you weigh your lighting, water, waste, testing will show you what you need to add or could lessen. I wouldn't consider food to contribute unless you overfeed.

 

[Pinkey]

Wow, such great information over one night! Thank you already.

>Btw, what's your tank setup?



135g
For reference, this tank is 6' across.
The gutters behind the tank are each 4' across.
The tank is open topped: the wood frame extends beyond jump range
Mag 9.5 w/ venturi pushes water 6' up to the top planted gutter (200 gph at head).
Mag 9 pumps water from 20g DIY sump (2 layers of blue filter pad & 1 cf of lava rock)
Total flow is approximately 700 gph: just over 5x per hour
Water pumped into tank from sump via PVC spraybar to minimize dead spots and disturbing the sand
Sump returns through two 3/4" DIY units
Playground sand substrate: 3" deep in mounds and bare in the places the catfish like to stay. I'm hoping the val will anchor the sand after the next lighting upgrade.
Some of this sand is acting as a deep sand bed and should be helping with the nitrate breakdown.
2 60w light bulbs in clip on desk lamps for lights (until next upgrade)

Fish:
3 x 7" oscars
1 5" bichir
2 8" pictus cats
1 parrot fish (found on doorstep in bucket one summer)
1 8" Jack Dempsy
1 10" albino Plec
1 crawdad brought over by a neighbor kid

Aquarium Plants:
Java Fern: there is not enough light for it to grow but it just won't die.
Val: anything close to the window to the left of the tank will stay alive.

Terrestrial Plants:
piles of lucky bamboo: 10+
pothos: 10' + It is growing at 3"-4" per week per vine at this point.
peace lilies: 12 plants over 4", the middle gutter is exclusively peace lilies.
Chinese evergreens: 1
a couple of spider plants: 2

>They are relying entirely on fish to feed the plants, and the plants to consume nitrates,
>as they don't practice water changes, or try to grow nitrate bacteria.
>Too many fish and the plants can't keep up with the nitrates, too few fish and the plants don't get the optimal amount of nutrients.

Precisely!

>Water can be stabilized with no filtration at all, but not with ease.

But it can be done. . .I am happy to have filters and equipment and whatnot. Part of the thrill with this particular setup is to see if I can stabilize the system and add only water to replace what has evaporated. At present, with the gutters, aeration, and open top I add about 5 gallons per week.

>Call me a planted tank nut

You and me both.

>There really isn't such a thing as too much biomedia

But there is such a thing as wasted space. If I need the biomedia I am happy to use it. If it is redundant for the bio load and will never be used I could use that same real estate in the aquarium stand, for a deep sand bed or even for just a water reservoir to increase the total gallons and keep the sump water level more stable. If I find the perfect balance for everything I would just store a bucket and hose in there.

>I personally have never heard of anyone being able to maintain plants in a tank of Oscars.

Understood. Most of the plants are not in the tank. I have a 55g that produces enough val that even if the oscars keep it trimmed I can replace it. So far they haven't had much interest but I know that can change on their whim.

>Once you weigh your lighting, water, waste, testing will show you what you need to add or could lessen.

The plants are enough to metabolize nearly all the nitrites and ammonia. Those show up as trace amounts. The nitrate is the one that builds up over a couple weeks. I will add anything necessary with the goal of a balanced system in mind.

> I wouldn't consider food to contribute unless you overfeed.

I wouldn't have thought of it this way before reading aquaponics info. Most aquarists measure a system based on its ability to process fish waste. Aquaponics science begins measuring the food introduced into a closed system. The food turns into the waste. They know that in their systems X kg of food will turn into a certain nitrate reading. Reduce the food to reduce the readings. It doesn't matter if that food is eaten by 10 fish or 10,000 fish. It is the food that turns to waste.

Since I am not willing to modify my concentration of fish (I am not growing them to eat) I have to modify the system. I want to feed the fish enough that they are happy. Happy fish is my primary goal. I would love to be one of those people who has 20 year old oscars who have perfect health and no Hole in the Head.

I hope this information helps clarify things. Thank you all again for your time and expertise.

 

[stingray4540]

Haha, I see you combined responses from your other thread to this one, threw me for a loop for a second.

One question I have about the system, why the open top? If you have any DIY abilities, with a screw driver and some wire strippers you could add a top to your top and install a lot more light for pretty cheap.

Oh, and I have to agree with your thoughts about too much media. As has been stated, you can't have too much, but if you have a lot more than you need, you could be using the space for something else. Between the 20 gal sump and the plant media, I think you have more than enough bio media.

 

[FreshyFresh]

If your filter can't push water through it, it's too much.

 

[excuzzzeme]

I wouldn't consider food to contribute unless you overfeed.

I was referring to food that is wasted and not processed by the fish. Normal feedings and its subsequent waste is a given. Overfeeding or excess feeding is a commonly overlooked problem that can greatly affect the water chemistry. Goldfish for one, do not process food in the "normally understood mechanics", They benefit from more feedings of a lesser amount vs fewer feedings at a greater amount. Either way, uneaten food can collect in the substrate and impact water quality vs no residual food. Naturally, there is going to be a certain amount not eaten no matter what you do. Ever seen an Oscar spit food out it's gill covers? LOL, a very common occurrence.

Have fun and enjoy your project!

 

[Pinkey]

Mr. Ray,

I chose the open top so plants could grow out of the aquarium without getting pinched as they do with a standard top. The open top gives me a lot of freedom that I have only had in ponds in the past. I found several lighting solutions that I can suspend above the top frame and still leave the top open (I'll buy them next time I have the cash). Besides, I really like looking down into the tank at the fish. It is somehow more lake-like to me. If you haven't done it in a while, look into one of your tanks from the top for a while. It is a whole new view and I really like it.

>Haha, I see you combined responses

One of my jobs is writing so I have learned to combine to save time when possible . I figured a more accurate title would catch the attention of the people who have more to say on this subject.

You and Mr. Me happen to be people who have interest in both.

Nate