tank getting very dirty

[fatboy]

My 5 gallon cherry red breeding tank is becoming very dirty. It's filtered by a small sponge filter powered by an airpump. Since it's a breeding tank I don't vacuum often and chanmge about 50% water once a week.

The gravel has a lot of fine dirt in it. When I vacuumed today it stank badly and surely can't be good. The water conditions are fine but I worry it will suddenly go bad.

I have been feeding them every day and wonder if that is the problem. The dirt looks like hikari crab food that hasn't been eaten. The shrimp look like they're eating it all but they're so messy perhaps a lot is sinking into the gravel.

Do you think I should cut back on feeding? I have 10 adults and 50-70 babies. They eat the food within 10 hours then go and nibble at java moss or the filter.

Any tips from experienced breeders would be appreciated. :)

[Lotus]

I think you should cut back on feeding. Shrimp have fairly inefficient digestive systems, so some of the food they eat comes out the other end undigested. The bad smell may come from anaerobic bacteria, so you might want to stir up the gravel occasionally, even if you're not vacuuming it.

[Walter]

Usually when it stinks it meant ammonia is present, your shrimps still doing well?

[fatboy]

Shrimp have fairly inefficient digestive systems, so some of the food they eat comes out the other end undigested.

That might explain why I've seen shrimp eat poo still attached to another shrimps behind. That was really disgusting.

I'll cut down on feeding and stir things up gently to keep the stuff from settling. I'll be careful not to overwhelm the filter.

Walter, there's no detectable ammonia. The shrimp are doing well. The only death was my oldest one, who was adult and bright red when I bought her. All the rest are active and appear healthy. That was a reason I was so shocked at the dirt - I don't understand how so much filth doesn't affect the water quality.