tiny organisms living with my shrimp: should I be concerned?

YuccaPatrol · Post by **YuccaPatrol** » Mon Apr 03, 2006 7:26 am

I've had my shrimp tank going for almost a month now. My Cherry shrimp are growing and reproducing and have had the first batch of shrimplets hatch this past week. All in all, they seem very healthy and happy.

I feed them very minimally and do a 20% water change each week. Water conditions are good: pH 7.2, nitrate less than 10ppm.

In the past couple days, I have noticed some tiny white colored organisms that cling to the glass and jump around. My guess is that this is probably normal and not a concern.

I have 6 fish tanks which in which I have never noticed things like this living in them, but I suspect that the difference might be that the fish tanks have more powerful filters without fine sponges on the intakes so the filters would remove them from the tanks before I would even notice a population of tiny but visible micro-organisms on the glass.

Is this just a normal condition of a shrimp tank or is it something I should be concerned about?

frugalfish · Post by **frugalfish** » Mon Apr 03, 2006 7:40 am

As tanks age you'll find all kinds of little critters making it their home. I find that my planted tanks seem to really have the most life. I have never had any problems and actually find the little ecosystems interesting. Common things you'll see are cyclops, planaria, little worms, rotifers, and other such creatures. These populations will rise and fall depending on the aquarium conditions. Excess food will definitely cause certain populations to grow. I think these organisms are more apparent in shrimp tanks due to the lack of predators that would normally eat them.

bulrush · Post by **bulrush** » Mon Apr 03, 2006 8:50 am

Sounds like you have cyclops. Do a search on Google Images and you can find pics of them. They are about pinhead size, I have them too, and they like to cling to the glass then jump through the water. The females (with eggs) look like a raindrop with 2 bags behind them, which makes them "Y" shaped. Males have no bags (which are egg sacks).

YuccaPatrol · Post by **YuccaPatrol** » Mon Apr 03, 2006 9:33 am

bulrush, your description of cyclops is exactly what I have. Thanks!

I had noticed the teardrop shaped ones and thought they were cyclops but did not know what the ones with the little bags behind them were the same.

I do think it is interesting and neat to have the diversity of organisms just show up on their own.

Post by **Mustafa** » Mon Apr 03, 2006 2:18 pm

I have tons of copepods (="cyclops") in many of my tanks in addition to all kinds of other little creatures and worms that appeared by themselves. Copepods like very clean water so they are good indicator species.

frugalfish · Post by **frugalfish** » Mon Apr 03, 2006 3:43 pm

Copepods like very clean water so they are good indicator species.

I really don't know anything about copepods and I find that interesting and true concerning my shrimp tanks. The tanks that I have the highest concentrations of these creatures are the ones that have no measurable nitrous waste. Cool.

8x10 · Post by **8x10** » Mon Apr 03, 2006 5:07 pm

Does that mean I shouldn't be removing them?

I didn't like the way the tank looked with a whole lot of these and was worried they would harm my shrimp. (I'm still new at what cherries like and don't like). I've been sucking them out with a turkey baster. I thought they were a sign that my water was bad and was maybe over feeding although I only feed every couple of days. Thought lots of extra critters came from that

frugalfish wrote:
Copepods like very clean water so they are good indicator species.
I really don't know anything about copepods and I find that interesting and true concerning my shrimp tanks. The tanks that I have the highest concentrations of these creatures are the ones that have no measurable nitrous waste. Cool.

shrimping · Post by **shrimping** » Mon Apr 03, 2006 11:01 pm

You can put in some small boraras to eat them.

frugalfish · Post by **frugalfish** » Tue Apr 04, 2006 7:23 am

8x10 wrote:Does that mean I shouldn't be removing them?

There's no reason to remove them as they are harmless, but if you do remove them that won't do any harm either.

Post by **Mustafa** » Thu Apr 06, 2006 1:08 pm

frugalfish wrote:
Copepods like very clean water so they are good indicator species.
I really don't know anything about copepods and I find that interesting and true concerning my shrimp tanks. The tanks that I have the highest concentrations of these creatures are the ones that have no measurable nitrous waste. Cool.

See? You just confirmed my hypotheses.

I've been observing this for a long time actually. The copepods disappear when the nitrate and ogranic load in the tank gets too high. They appear again after the water parameter issues have been corrected. They appear to have dormant eggs that get activated when the right water parameters are present. AND...in large numbers they take care of all kinds of algae problems on the aquarium walls and elsewhere.

badflash · Post by **badflash** » Thu Apr 06, 2006 3:03 pm

I've been observing this for a long time actually. The copepods disappear when the nitrate and ogranic load in the tank gets too high. They appear again after the water parameter issues have been corrected. They appear to have dormant eggs that get activated when the right water parameters are present.

Forget the hypothesis, it is a fact. When conditions get poor they produce "resting eggs" just like daphnia do. When the conditions get right, they hatch. They can't tolerate nitrates. When I stop seeing copepods in my shrimp tanks I start to worry and get out the test kit.

YuccaPatrol · Post by **YuccaPatrol** » Fri Apr 07, 2006 5:41 am

I am so glad I asked this question. I love the idea of having a biological indicator species testing my water for me!

Ok, I'll still test my water (of course), but this is really great info.

shrimping · Post by **shrimping** » Fri Apr 07, 2006 8:19 am

What about hydra? Do they have a dormant state when he water condition is not right too? I had hydras in the tank before but they disappeared by themselves, are they just waiting to make a comeback?

badflash · Post by **badflash** » Fri Apr 07, 2006 3:14 pm

Hydra reproduce primarily via budding, but do have the ability to reproduce sexually. The eggs can take from 3-10 weeks to hatch, so it is possible that they could make a come-back.

Moni · Post by **Moni** » Thu Aug 23, 2007 1:37 pm

I have copepods in my crs tank and I was begining to get worried. In one of my aquarium books Baensch Aquarium Atlas 1 I read that they are gill flukes that can kill fish. The gill fluke one is Ergasilus sieboldii or "paddefooted crab". I'm guessing the ones in the shrimp tank are a different and hopefully harmless species of copepod or cyclops. There are no fish in with them. My shrimp are doing well and I have 18 of them that were shipped to me over a month ago. So I'm glad to hear that these creatures are a good sign. Could they have come from the oak leaf litter I added to my tank?
Moni