How much tank for a given bio-load?

[DJRansome]

I'm intrigued by zoanthids, the button polyps and considering a tank to showcase them. Of course, what's a showcase without a complementary fish or two?

The project is still a ways in the future. I've kept freshwater Malawi cichlids for 2 years in a 125G tank, and I'm just putting together a 38G planted freshwater Tang tank. Half the fun for me is in the planning!

I'm debating between a smaller tank with just the zoos, some green star polyps and a pair of pseudochromis fridmani. Or going all out with whatever it will take to house several favorite fish species. (I know, I know, buy the largest tank you can afford.) How do you calculate tank-size for a particular bio-load? I've done some reading and get the basic concepts of sumps, skimmers, live rock and sand, halides, etc.

I still only want the zoos and green star polyps. But what size tank would I need if I wanted the following:
3-6 chromis viridis
3-6 chromis cyanea
2 pseudochromis fridmani
2 banggai cardinals
2 neon gobies

 

[Anonymous]

Well, that's a tough question as there is no tried and true formula as to how much bioload is too much. Also, bioload isn't the only problem, territoriality can come into play, even with docile damsels like the chromis. Adequate swimming room plays a role as well as what type of setup you choose. I hate to give vague answers, but the only way to figure it out is almost "instinctive". That comes from watching many tanks crash and muttering to yourself "I shouldn't have" or I should have" :lol:

If I had to hazard a guess, I'd say you could do it with the low end chromis figure (3 of each species) in a 90. The banggai can get quite nasty if they form a pair and brood, and you'd have to add both orchids at the same time as they are quite scrappy one to the other-and can be tough on tankmates as well.

Here's a great article on the different types of chromis and compatability:

http://reefkeeping.com/issues/2003-11/hcs3/index.php

 

[DJRansome]

OK, what size tank for the other extreme? Green Star Polyps, Zoos and a single Pseudochromis Fridmani?

 

[Anonymous]

That could easily be done in a 29 gallon IMhhO. Corals that are mostly photosynthetic (as opposed to say LPS that need meaty foods which add extra nutrients to break down) don't add that much to bioload. All you'd have to figure would be the fish's space requirements.

If you like planted tanks, one of our members is setting up a beauty in this thread:

http://www.reefs.org/phpBB2/viewtopic.php?t=110040