Random question......

[Pseudomugil]

I've always wondered why in saltwater, stocking must be much lower than freshwater. For example, in a 50 gallon freshwater tank you could get a big school of fish, a group of larger fish, a centrepeice, and just a ton, but in saltwater you could only get like 5 or 6 small fish. Does anyone know why this is?

 

[Sniperhank]

Bioload aside, understand that many of the fish we keep in saltwater are open water swimmers and need a ton of room to simply be healthy.

 

[Pseudomugil]

Ya i know, but like clownfish for example. Do not need a lot of swimming room, but 2 takes up the whole bio load of a 15-20 gallon tank.

 

[bribo12]

Clowns actually do swim a good amount unless they have a host nem or coral. They can also be little buttheads as many sw fish tend to be more aggressive than their fw counterparts. Also sw tanks can't handle bioload a like fw tanks can. So 2 3" fish in a 15-20 gallon is quite the bioload for a sw tank.


Sent from my iPhone using Aquarium Advice

 

[Pseudomugil]

Clowns actually do swim a good amount unless they have a host nem or coral. They can also be little buttheads as many sw fish tend to be more aggressive than their fw counterparts. Also sw tanks can't handle bioload a like fw tanks can. So 2 3" fish in a 15-20 gallon is quite the bioload for a sw tank.


Sent from my iPhone using Aquarium Advice

Yes I know but I'm asking why is that? I was just using clowns as an example.

 

[Ingy]

Salt water actually holds about 20% less oxygen in solution than does freshwater. Also, warmer saltwater tanks hold less oxygen than the slightly cooler freshwater tanks do. So, together, this means salt water tanks hold about 70% of the O2 levels that freshwater tanks do.
Combine the lower O2 levels with the higher O2 requirements of reef fishies (5-8mg/l O2) as compared to the levels of some of our favourite freshwater fish that only need 2mg/l O2, and you get a much less crowded salt water tank.

 

[Sniperhank]

This thread fell off my radar during my work week. Basically, it isn't true for ALL fish in saltwater. Gobies are a great example of this in general. But these guys are really small fish and like to perch and hang out. The rest overall either get really big, need a ton of swimming room, and this and that.
This can be said for freshwater too. There are large freshwater fish that simply need a ton of room, be it size, distance swimming, or aggression.
In general, one needs to understand the fish you are trying to keep to understand what it could be kept in. A trout wouldn't work in a 55 gallon tank as much as a tang doesn't belong in one. It is a really good understanding on how inch per gallon rule doesn't work no matter what type of water it is. It is easy to have a view of saltwater only needing big tanks as there are more fish that need the room that are sold in the hobby where freshwater has a ton more fish available for smaller tanks...really makes me want a planted tank full of tetras.

 

[Gregcoyote]

You can pack a lot of small SW fish into a aquarium if your filtration is up to the task. As mentioned, SW contains less dissolved oxygen, but effective aeration and maybe a oxygen generator (which I am testing) can help take up the slack.

Most people recommend fewer fish as most folks don't have the filtration for more.


Sent from my iPhone using Aquarium Advice

 

[Pseudomugil]

Salt water actually holds about 20% less oxygen in solution than does freshwater. Also, warmer saltwater tanks hold less oxygen than the slightly cooler freshwater tanks do. So, together, this means salt water tanks hold about 70% of the O2 levels that freshwater tanks do.
Combine the lower O2 levels with the higher O2 requirements of reef fishies (5-8mg/l O2) as compared to the levels of some of our favourite freshwater fish that only need 2mg/l O2, and you get a much less crowded salt water tank.

Thanks this is the answer I wanted. I just didn't understand why.

 

[PB_Smith]

You can pack a lot of small SW fish into a aquarium if your filtration is up to the task. As mentioned, SW contains less dissolved oxygen, but effective aeration and maybe a oxygen generator (which I am testing) can help take up the slack.

Most people recommend fewer fish as most folks don't have the filtration for more.


Sent from my iPhone using Aquarium Advice

yes and along with that keep in mind that if you are going by sources such as live aquaria.com, they give the safest recommendations allowing for a large margin of error, same with aqadvisor.com.

Many will say my tank is overstocked with 10 small/medium fish in a fifty.
But with good rockwork/scaping that provides everyone with a place to call "home" and judicious stock selection, they are all doing absolutely great.
Plus I do have filtration on here capable of supporting a tank twice this size.

It also depends on if a person is keeping coral or not. In a fish only tank you can stock it heavier because the fish are not as delicate when it comes to nitrate and phosphate levels. So often the low stocking is an attempt to maintain as pristine parameters as possible in a reef system for the sake of the corals.

 

[Gregcoyote]

Everything in the ocean seems symbiotic. The fish need the corals and the corals need the fish. There is a natural balance struck on a healthy reef and that's similar to the balance you need to attain in your closed system at home.


Sent from my iPhone using Aquarium Advice

 

[TheTodd]

Going along the lines of what PB said a couple posts up...you can probably get away with more fish in a fish-only tank (which is what a lot of FW essentially are) because the parameters do not need to be so perfect. Corals need those more pristine parameters.


Sent from my iPhone using Aquarium Advice