I understand the 10 gallon/fish rule...but?

[Nathan]

Ok, I have a 75 gallon tank ready for Discus. I am going to get at LEAST 7 2.5-3" Discus and grow them to adults in this tank. I do not want to push the envelope :-\ but would 8 adults do good? What about 9 or 10?

BTW I have two Hydros.

[brewmaster15]

Hi Nathan,
What kind of water changes would you be doing and do you any other filters running except the hydros? Also what would you be feeding?

-al

[Carol_Roberts]

That's a good sized tank, you have room for lots of babies. You could grow out 12 or 20 babies as long as you are willing to thin the herd as they grow. Sell the rest a few at a time and keep your favorite 7 or 8.

[mench]

I have a 75 with 20 juvies in it some of my 55 have 7 adults.my 110 will have 16 semi adults in it,but I do water changes every day.Yep the 10 gal per fish is a good rule but depending on water changes you can go a bit over,in my opinion, my tanks will be a tad crowded till they grow up and start to pair then some get moved to breeding tanks and others will be sold off and the tanks will be semi empty and then hopefully fry will be around and we start all over again...or we tell the bride it's time to set up all those extra tanks we have stored Hee Hee

Mench

[Nathan]

Thanks for all your help :) I am going to get 8 juvies to grow out. All I have are the Hydros running. I'll be doing daily w/c's. Also I'll be feeding frozen bbs, beefheart, Flake, and tetra colorbits.

Thanks again!

Nathan

[JeffreyRichard]

I hate the term "10 gal per fish RULE" because it's not a rule, but more of a guideline to start with when keeping discus.

While I'm sure that there is some ABSOLUTE MINIMUM tank size for keeping adult discus, I believe it is much less than most people believe. I actually raised THIRTY FIVE (35) Red Turquoise discus in a 75 gallon tank. The largest males were better than 7 inches (at least 8 of them), and I was getting breeding pairs at 11 months. Thats about 2 gallons per fish ...

The reason why I was able to do this had a lot (understatement) to do with the 90% daily water changes.

What I'm leading to is this ... there is a relationship between environmental factors which affect the success of a discus tank. You need to find the point where your factors maximize this.

If you can do 100% water changes daily, you can pack more fish into a smaller area.

The quality and quanity of filtration will raise or lower the amount of fish you can keep healthy.

The chemistry of the water also plays a role ... better water (softer/acid) gives you more margin for fish.

So ... if you had to map out what factors give you more fish, it would be something like this ...

LESS FISH MORE FISH
__________________________________________________ _________

small water changes frequent water changes
small qty water changes large qty water changes
less feedings more feedings
no filtration high filtration
small tank big tank
hard water soft water
Alkaline Acid

[mench]

Good advice Jeff.

Mench

[April]

great advice. except...if its extremely soft water like mine...then with a high load of fish your ph slides very very fast. so then youd need a buffer. as all those little gills and bioload are giving off alot of ammonia.
But most peoples water isnt as soft as mine.
With large daily wc then your ph does stay more stable.