How many fish is TOO MANY? 20? 40?

herring_fish

Crazy Designer
I have twenty two fish in a 6 foot 130 gallon very mix reef tank and I'm thinking about getting more. I will talk about filtration below on back ground but I am mainly interested in the impact on fish behavior in an environment of good water quality and more than adequate feeding. Possible over crowding could change normal interactions in the tank so if I pick compatible fish but go to thirty or more, what problems would I be looking at, not counting water quality or coral health. That is a separate discussion that is open to so much more debate that would be better handle in a different thread.
So "¦.what about too many fish in a 6 foot tank.


Rambling back ground that you can skip if you are not concerned about nutrient load:

After several years, my tank has been restarted and is now about one and a half years old. I have had a 55 gallon sump hooked up for about 9 months that is filled to the top with a special coral rubble from Caribsea that is very porous. Unfortunately, they do not offer this for sale. I am also re-using a dump bucket style Algal Turf Scrubber (ATS) that saw about 10 years of excellent service in my old tank. It doesn't grow much algae this time so I still have a lot of capacity yet to fill.

I feed the fish a lot of foods of different types but this is a reef tank first. I feed the filter feeders about 12 pinches of powered food once or twice a day. I know that this is an inaccurate measurement but let's just say that it is a lot and yet I don't have any hair algae in the tank at all. Unfortunately, the rock does not grow much coralline algae enter, despite liberal supplement dosing. This is an issue that is sometimes reported in tanks that dose vodka.

I think that adding Reef Bugs into this tank that has so much coral rubble is keeping nutrient levels so low. The scrubber is not doing the lion's share of the work. It is almost being starved. I guess that it is like adding vodka only safer. I see super fine strands of white bacteria growing around bottom rim of the tube that the ATS bucket dumps its water into. I use them as a guide to whether I need to increase or decrease the input of the Bugs.

I don't to any skimming at all and have no form of mechanical filtration because I want to keep foods suspended as long as possible. What settles out is processed by critters and bacteria in and on the deep sand bed. I do place carbon in a sock but water is not pumped through it.

Upon reading this back ground, I know that some people are pulling their hair out but it works for me so why knock it? Now, back to the fish?

I have 8 Cromis(s)?,5 Clowns, 3 Tangs, 1 Manderan Goby, 1 Royal Gramma, 2 fire fish, 2 Damsels, several crabs, shrimp, stars and clams.
 
You will have more room for fish as your chromis and clowns widdle themselves down to pairs. What are you thinking of adding? What kind of tangs do you have? How much live rock is in your tank? Your filtration is a different animal than mine, but there is more than one way to skin a cat as they say. Your current set up does not sound too bad compared to other's I've seen. The more fish, the more maintenance, and if it were me, I'd be skimming with 3 tangs in that tank. If you add more fish expect it to effect water quality and increase the amount of water changes which takes time and money. If there is aggression you could lose a pricey fish or one that you are attached to. I'm not gonna knock it, but I wouldn't try it.
 
I have 8 Cromis(s)?,5 Clowns, 3 Tangs, 1 Manderan Goby, 1 Royal Gramma, 2 fire fish, 2 Damsels, several crabs, shrimp, stars and clams.

5 clowns will like result in 2 clowns; 8 chromis are likely to winnow the herd to s smaller number; 2 firefish, unless a mated pair, will likely become 1 firefish. The damsels or clowns may eventually intimidate the firefish.
 
Most of the fish have been there for months. I have a blue, a yellow and a yellow eyed tang. I want a Powder Blue Tang, a female mandarin goby (I have the pods), several Anthias and more.

All the fish play nicely except one small Percula Clown gets picked on from time to time by one of the four. They don't know to use an available Anemone. The fifth is a big yellow striper but it has its own Anemone that it does use. It is the newbee but has not fought at all. The Damsels play nice as well, near the bottom of the pecking order.

Again water quality is not an issue and shouldn't be with more load.
 
With fish yes they swim in the water so good water quality is always helpful to the fishes health, but IMO what's more important is space so swim! I'm sorry your current tank does not have that for your current fish list not to mention the fish that you have will likely be killed or kill each other as they mature...I sugest a larger setup before you think of more fish.
 
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Guys, We've seen these threads before, just search for them. I doubt he's looking for any advice, just wants someone to agree with his logic and planned additions which makes it alright to overcrowd a tank.
 
the chromis will kill eachother until there is two, firefish will do the same. I have had 4 clowns in my tank for over a year but that 5th one you have will be toast. I would not add anymore tangs. Also cut back on the feedings 12 pinches 2x daily is to much. without a skimmer with that bioload you are going to crash your tank or at the least kill your livestock. If you want to keep a heavily stocked tank you need a good skimmer and bi weekly water changes. I find it hard to believe that your tank has been set up for so long without nitrates through the roof. I keep a well stocked rank and i really work hard to keep my nitrates down
 
the chromis will kill eachother until there is two, firefish will do the same. I have had 4 clowns in my tank for over a year but that 5th one you have will be toast. I would not add anymore tangs. Also cut back on the feedings 12 pinches 2x daily is to much. without a skimmer with that bioload you are going to crash your tank or at the least kill your livestock. If you want to keep a heavily stocked tank you need a good skimmer and bi weekly water changes. I find it hard to believe that your tank has been set up for so long without nitrates through the roof. I keep a well stocked rank and i really work hard to keep my nitrates down


If anything, the 5th one will be the sole survivor. lol If it is in fact a gold striped maroon clown like I'm guessing it is. Not to mention it's a gsm WITH an anemone to defend. If the percs try to invade it's territory, or even go too close to it for that matter...the gsm will regulate. ;)

And as others have mentioned your tang stock is filled up, the chromis will wittle down, the firefish may or may not work, and without skimming your tank is not on the right path for the long haul with that feeding regiment. I know you think your tank is huge because it's 6 foot and you think it's successful because it's been 'setup for months', but neither is true. 130 gallons is not that much and a few months isn't that long. Anything under a year isn't even established yet, and might not even be completely stable. The fish (especially the tangs) will get more aggressive with age.
 
I was afraid to by the Striped Damsel from a friend and it used to be aggressive until the blue tank was in the tank for three days. Then the tang put it in its place. Now it has a small territory that is at the back of the tank and it is very docile. The blue Damsel with a yellow tail mostly hides but give never gets any grief from any thing that I can see.

One fire fish hides about 60 percent of the time and the other about 80. They may be fighting like mad behind the rocks but I don't see that.

I just got the big yellow striped clown with its Anemone. I was also afraid that it would cause trouble because of its size but it was a steal so I took a chance. It has peacefully stayed in its lair without incident.

When I put new arrival in the tank, it hung out with the other clowns for an hour or so before I turned out the lights the first night. They all started waggling and rubbing against each other. I though that this was very strange. In the morning it found its Anemone and never leaves it ow. It has been in the tank for three days and doesn't leave the Anemone. It doesn't look afraid at all, just happy as a pig in its mud.

I did however notice the resumption of the bigger Percula picking on the smaller one the first full day that the new Yellow Striped Clown was in the tank. This introduction seemed to trigger that behavior. That is the only reason that I started this thread. I have seen this interplay between these two fish before and I hope that it goes away again. If not I will have to catch and give away the small fry. It still seems to be eating quite well.

Perhaps the fact that I bought most of the fish from friends has made for a more well adjusted tank population. I wouldn't think this would be a big factor but maybe. This excludes the 8 Chromis, the Yellow and the Yellow Eyed tangs, the fire fish and the goby.
They were store bought.

There have seen many studies on rat populations, ants and others, that show that if you restrict the allotments of food in an enclosure, the population will fight to the death until the population matches the allotment of resources at hand. Perhaps, fish can detect water parameters deteriorating in an over crowded tank and become aggressive. This has not been the case in my tank as yet. I am open to advice on what to look out for.
 
Guys, We've seen these threads before, just search for them. I doubt he's looking for any advice, just wants someone to agree with his logic and planned additions which makes it alright to overcrowd a tank.

:worried2: Agreed. To each his own. I would remove the chromis and maybe 3 of the clowns to gain more space. Its easy to really pack a fish only tank because high nitrates aren't much of an issue, but there is no way you would be able to keep coral in a tank that full, long term.
 
Choose between the gold striped maroon clown or 2 percs. the other percs will be killed. Eventually the chromis will kill one another off. Dont add more chromis. The damsels will become territorial and harass just about all the fish on your list. When a firefish dies don't replace it. It is likely due to aggression that you are not seeing. They are a very timid fish for the surroundings(tangs, clowns, damsels). There have been a lot of studies of saltwater fish in aquariums. I read about them on reefcentral every day. You are making some mistakes that would not have been made had you done a little research.
 
Ok I can see the fire fish dieing. Now and honest question. Will the Yellow Stripe kill the other clowns when it starts to feel comparable? I can see that too. Why will the Chromis change there temperament and start killing each other? Is it a seasonal thing or The Night of The Living Dead? I said that the Damsels are not acting aggressively. They have been in the tank for a long time and they have not changed. I can see the Damels picking on newly introduced fish that are under stress but not once they are comfortable in the tank.

"¦and the corals are just fine thank you. With custom formulated foods, low nutrients, good water motion and good lighting, what will hurt them, not the fish, not the fish waste

Come on guys and gals, are there any real concerns that I should look out for? The Powder Blue is a finicky fish and big one so it might be the straw that brakes the camels back. Will the Anthias fight with the Chomis or elicit and adverse reaction from any other fish?
 
Guys, We've seen these threads before, just search for them. I doubt he's looking for any advice, just wants someone to agree with his logic and planned additions which makes it alright to overcrowd a tank.

I think the OP may be a bit of an exception to this rule. They're hanging in there with the thread and not getting offended about the advice.
 
if you go slow and test you water will tell you what you can do . it is not wise to just fill a tank with a bunch of fish as you should have a planned end in sight at all times . you want to many fish and i would suggest that you heed some of the suggestions above or you will simply be killing fish and thats not responsible fish keeping in my world .
 
I have been adding fish and corals slowly and I have steadily adding to the amount that I feed. I don’t know if you mean that I might be offended by advice but I’m not. When you go in a different direction, I expect to get criticism and some of it is well founded. I am however good up until last weekend. The fish were happy and the corals were happy. I know that it may be hard to believe but that is where I was, 21 fish worked quite well. I guess that most people believe that I am deluding myself. Looking back I don’t think that it is true. As for the future, I may be pushing it too far. I am a professional experimenter so I will push the envelop and I ask for help in doing so. I don’t want to kill anything and have had good luck so far. I am looking for caution signs and help with selection. If a safe number for you was 10, what would you look for when you get to 8?

Now I ask again, is the Yellow Stripe bad news in my situation? Will some Anthias interact badly with the other fish? I may very well be at my tipping point. What do I look for?
 
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first nitrates will be hard to control then you will start having hair algae and cyno blooms along with low alk readings .once you see this happening then be on the lookout for ammonia and then its over for the less hardy specimens . i have 45 fish in 5 tanks which add up to 250 gallons in tanks but i have 200 gallon sump with a 75 gallon refuge and i have no hair algae .ph 8.2,0 phosphate ,0 ammonia,0 nitrite, 10/20 nitrate and have stable 8 alk .so i am good now but i do have a large bio load and my cheato grows like a weed . i do 60 /80 gallons a week water change broken up into two 30 to 40 gallon each week at different times in different tanks . every tank gets cleaned every other week pretty well and the system gets a 60/80 gallon a week water change and this keeps it all very clean .skimmer produces 1 pint of scum a day and i use a quart of carbon every two weeks .i used to use gfo but my cheato has mad it possible for me to stop its use which saves alot of money .yes i go through salt like mad but its worth it all to me .
 
The yellow and white is a clarki they get mean as hell as they mature .Its not that your stocking levels are way to high it is just the temperment of some of your fish. clarkis and maroons are very aggressive.
 
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I have been keeping clowns pretty much since I started this hobby (( 1992 )), and one thing that I have learned is any more then one pair per will end up, in time, back down to one pair (( at least in my experience )). I have tried more then 2, and nature took its course, and I ended up with just the pair.

IMO, you should do your fish a favor and pick a single pair of clowns and stick with that.
 
Toddrtrex
Well, one from the big pair is picking on the smallest of the other pair. I have had them for over a year and have seen that behavior a few times but its much worst now. I may have to fish two out.

What about the big yellow strip? Oh ...by the way. The little one that is being picked on has been hanging out near the yellow strip and the yellow is coming to the rescue of the small one, leaving its Anemone to chase the dominant Percula away. It doesn't follow up. It just comes out until the Percula takes off and then returns to its home base. That's the only thing that brings it out and only for a second.

lisafoster
Sorry for my ignorance. What do you mean by clarki? I had a Maroon in my old tank and had to get him out because he was too aggressive just like you said. My yellow strip is BIG already. Do you think that it is docile only because it is new to the tank and once it feels at home it will start acting out?

Thanks to you both for the behavioral advice.
 
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