thinking of adding clowns to my 90 gal (us) / 340 litre tank

[tfmaxman]

I've got a now mature (6 months old) cycled tank to which I'm thinking about adding a set of 5 clowns loaches. It now has 2 silver dollars, 2 jack dempseys and 4 giant danios. All my water tests have had great readings for four months (nitrates 20 ppm or less, 0 nitrates, 75-100 ppm hardness (gh), 120 (kh), 7.2-7.8 ph.

I'm relatively new to the fish-keeping scene. I started out with Oscars (just 2) and had a dreadful time. Adding just one other fish to the scene caused HITH, even though I did frequent water changes and with lots of filtration. I've got two tanks (one smaller 55 gal). Anyway, no more oscars. I've got a stable environment now with healthy fish. So I'm hesitant to add anything.

The tank is relatively bare. A few pots for caves and hiding, sand substrate, and a large-ish bogwood decoration, an air stone. Rena XP3 filter. Regular water changes.

I'd love to add a group of clowns but I'm concerned about 1) the bioload on the tank and 2) the risk of adding fish to my stable environment. I would add some smaller hiding spaces for the clowns to hide. The jacks are pretty docile and have left the danios alone, so I'm not concerned about that.

I've really valued the advice given here. My 55 gal. tank at work is thriving with a group of weather loaches that I really enjoy. Any and all opinions on how to proceed (or if to proceed) are welcome.

thanks,

todd

[bslindgren]

I'm surprised nobody responded to this earlier. Knowing what I know now I would not add clown loaches to that size tank unless I had serious plans to upgrade later. And adding them to a tank with Jack Dempseys is probably not a great idea either, although a lot of people seem to keep cichlids and various loaches together. There's a reason after all they are named Jack Dempsey after the famous heavy weight boxer!
I don't think five clown loaches would create a problem in terms of bioload, assuming you have semi-decent filtering. Particularly since it's rather difficult to get them at a reasonable size - you don't want to buy anything smaller than 2 inches. I have a tank slightly larger than yours with way more fish (no doubt too many) and it is stable. I have lots of plants and aerator.
You need to quarantine and medicate any new loaches - they often come in with internal parasites, and they are incredibly susceptible to ich. I'm not sure about the temperature requirements of the cichlids and the silver dollars (I keep giant danios and they seem fairly adjustable), but clowns want high temperature and lots of water movements, plus lots of caves and hidey holes.
If you really want loaches, I would probably recommend a slightly smaller species than clowns, even though I dearly love my own clowns (most of which I bought largely as a result of ignorance I confess).

[Diana]

Ditto: Quarantine, medicate, and larger tank.

[chefkeith]

I don't think clown loaches make good side kicks. If you want to house clowns, they'd prefer to have a tank specific for their conditions. You'll need lots and lots of water flow (about 4x more than what you currently have) low lighting, lots of ground cover, plenty of driftwood, an acidic pH, low hardness, and tank mates that are not aggressive feeders. Clowns will thrive when they're the main attraction.

You'll need to upgrade the filtration also.