Can fish live without a filter????

[Fishingandreefing]

I have about 5-7 fish in a 27g container with a bunch of live rocks, heater and a powerhead. If I change out about 15% water weekly, will this be ok for a while?

 

[chaostactics]

It's dicey but possible.

 

[Bccarty151]

Do you have sand? Test kits?....if so watch the parameters and the fish...may have to adjust water changes accordingly

 

[chaostactics]

It's dicey but possible.

If the fish are quite small and the powerhead is providing adequate gas exchange

 

[Tamberav]

I have about 5-7 fish in a 27g container with a bunch of live rocks, heater and a powerhead. If I change out about 15% water weekly, will this be ok for a while?

well live rock is a filter as long as it has flow.

Depends what the 5-7 fish are. That’s a lot for a 27g unless small.

 

[Ghost25]

Should be fine in terms of filtration if the live rock is mature and the fish are fairly small. I have 8 fish in a 20 gallon but gobies are small fish.

 

[WheatToast]

You could try adding moderate/fast-growing macroalgae (that won't get eaten) to reduce nutrient load and house microinvertebrates along with the rock. Remember to sustain adequate lighting, flow, and trace elements to keep them alive. Perhaps Cladophora, Chaetomorpha, and Codium could work (hey! they all start with c!).

 

[Fishingandreefing]

You could try adding moderate/fast-growing macroalgae (that won't get eaten) to reduce nutrient load and house microinvertebrates along with the rock. Remember to sustain adequate lighting, flow, and trace elements to keep them alive. Perhaps Cladophora, Chaetomorpha, and Codium could work (hey! they all start with c!).

That’s a good idea. Going to yank a small piece of live rock that has culerpa on it from the big tank sump lol

 

[WheatToast]

That’s a good idea. Going to yank a small piece of live rock that has culerpa on it from the big tank sump lol

OH BOY! Another algae that starts with the letter c!

 

[homer1475]

I ran a 40 breeder for years with nothing more then a heater, a couple powerheads, live rock, and sand.

Can certianly work 100% with 0 mechanical filtration. This is not freshwater, the live rock is your biological filtration.

 

[MaxTremors]

Should be fine, the only thing I’d worry about is proper aeration. I’d either ensure lots of surface movement or add a little air stone.

 

[Gtinnel]

If we are referring to mechanical filtration, then there are plenty of people running tanks without any, myself included. As already pointed out biological filtration is provided by the bacteria in the rock.

 

[InvertGang]

OH BOY! Another algae that starts with the letter c!

C is for algae, that's good enough for me...

 

[WheatToast]

Updates?

 

[Fishingandreefing]

I ended up getting a hob filter from a friend. But I am pretty sure if the ammonia level is not high enough to harm the fish, you don’t need one.

 

[Arthurfarris]

You can choose from a number of fish that can live without a filter, such as bettas, scarlet badis, guppies, glittering gouramis, etc. Of course, there are certain conditions that allow them to survive. They may exist, but they are a great option if you are starting an indoor aquarium.

 

[Spare time]

I have about 5-7 fish in a 27g container with a bunch of live rocks, heater and a powerhead. If I change out about 15% water weekly, will this be ok for a while?

You could always get an internal filter.

 

[Timfish]

Depends on what you call a "filter" Le CHin Eng decades ago made the observation corals are filters. Current research shows corals have heavy demands for nitrogen and phosphorus and show a preference for fish derived nutrients. Additionally, cryptic sponges have been shown to be essential recyclers and process labile hydrophobic DOC much faster than the bacterioplankton removed by skimmers and maybe more importantly also process the hydrophilic DOC skimmers can't remove. These systems just have empty unlit sumps and no skimmers, lit refugiums or reactors. Water changes amount to roughly 20% - 25% monthly.

90 Gallon Mixed Reef


Mixed Reef started in 1997, 10-07-19


220 Rimless 450 view


Here's some videos that might help informative:

Changing Seas - Mysterious Microbes


Nitrogen cycling in hte coral holobiont


BActeria and Sponges


Maintenance of Coral Reef Health (refferences at the end)


Optical Feedback Loop in Colorful Coral Bleaching


Richard Ross What's up with phosphate"


Figure 3 from rom Burkpile and SHantz paper "Context Dependant Effects of Nutrient Loading on the Coral Algal Mutualism"

 

[Azedenkae]

I have about 5-7 fish in a 27g container with a bunch of live rocks, heater and a powerhead. If I change out about 15% water weekly, will this be ok for a while?

This is actually entirely possible and probably what realistically happens in a lot of our tanks anyways, at least the ones that have the exact same setup except a filter and a powerhead.

Since your live rock is your main biomedia, really a filter is just an overglorified powerhead anyways.

Of course, if you have other biomedia, then it's a bit different. But I've seen people tie things like Poly-filter around a powerhead and boom - triple purpose: mechanical filtration, chemical filtration, AND powerhead guard lol.

 

[Arthurfarris]

You can choose from a number of fish that can live without a filter, such as bettas, scarlet badis, guppies, glittering gouramis, etc. Of course, there are certain conditions that allow them to survive. They may exist, but they are a great option if you are starting an indoor aquarium.

Some fish don't need a filter, but you have to do regular water changes to clean the aquarium water to their liking and your fish will stay healthy.