Bio-load Questions

[peter_griffin]

I am in the process of changing my bare bottom 75 gal into a planted show tank. I plan on keeping 6 adult discus 20 cardinal tetras, 5 pristella tetras, 3 sterbai cories , and 3 otto cats(will add after I get algae if necessary). I only want to do a once a week 25-30% water change. Right now the only thing I have are the discus and the pristella tetras. I plan on adding the rest of the fish after I have the Plants in there. Would that be too many fish ???? Could I add more :D? (I'd love to get a couple of Dwarf Flag Fish too)

[ChloroPhil]

I had bioload problems with 5 adult discus, 9 cory cats, 4 apistos, and 3 ottos in a 90g with a 20g sump. I would ditch everything but the discus and increase the ottos to 10. Expect to be doing 30-50% WC 2-3x/week with that load to keep algae at a minimum.

Best,
Phil

[Wolf_Mek]

You could probably do it if you did larger, more often water changes and added another filter or something to provide more surface area for bacteria. I would say 30-50% changes 3X a week.

Personally, I would stick to one specie of tetra and have the population at no more than 12 tetras. Having two shoaling species, IMO, can cause the tank to look "messy" in appearence with two shoaling groups intermingling and nearly running into each other.

[peter_griffin]

Lame :( ! I used to keep a pair of Adult discus with 10 cardinals and 3 otto's and 5 cories in a 40 gallon decorated tank(fake plants, rocks, and driftwood) with no real trouble (until my submersible heater went nuts and cooked everyone). I figured I could keep twice as many fish in a 75 gallon. Do Plants increase bioload? ??? Or is the fact that planted tanks are harder to clean the reason you can't have very many fish?

Thanks, Tom 8)

[ChloroPhil]

Neither to tell the truth. It's the additional light and nutrients given for the plants. Those two factors multiply the effective bioload of an aquarium many times over as far as algae is concerned. It's entirely possible to keep the number of fish you want in a 75g tank, but I wouldn't recommend doing as a planted tank.

Best,
Phil