Shrimps In Filter

[twintanks]

When I stocked my new tank a couple of weeks ago (after cycling, of course), I had not been considering having shrimps. Then I saw these cute little things scuttling about on the tank floors in the local fish shop and decided to have four. Now, I think they're cherry shrimps (I did look at the tank labels but was so engrossed in the fish at the time that I just don't remember!

). They are quite a bright pinky-red colour, very small.
Thing is....three of them have been just impossible to find since I put them all in the tank. One of them (Sammy) does come out for a quick spin around the bottom, but yesterday I found all of them in residence in the bracket that holds the Fluval U3 pump to the glass.
I don't know much about them and am wondering how they're managing to get food. I thought they might have been floor-scavengers, but so far they're just slumming it in the bracket.
My other fish are two blue dwarf gouramis and six neon tetras. I haven't seen them attempt to pursue the lone shrimp, so assume the hiding is not because they're scared. Do they ever actually come out? The ones in the fish shop tanks were all out "in the open", so to speak.

 

[Ch4rlie]

Well, it does sounds like they are red cherry shrimps from your description and these are very popular in most LFS.
 
Shrimps are very good at finding food and will happily eat leftover fish foods and micronutrients so not to worry about feeding them too much but would be good if you can occasionally add shrimp food every now and again.
 
Also, they are extremely good at hiding so spotting them is not always easy and can be a bit of an art finding them
 
And one last thing, gouramis do love shrimps as a tasty snack :x
 
Shrimps WILL hide from potential predators so this may be the most likely reason why your shrimps are behind the filter or hiding elsewhere amongst plants, having said that, filters and intakes are very popular with shrimps as there is lots of tasty foods for them around these areas.

 

[twintanks]

Oops. Didnt realise gouramis and shrimps don't mix....the shrimps were pointed out to me as suitable, after I'd selected the gouramis.

 

[Baccus]

Unfortunately most shops will say "yes cherry shrimp are fine to mix with X, Y and Z fish" meaning I think that the shrimp wont bother the fish and water requirements are going to be similar. However almost all shops over look the fact that almost everything fish wise is going to see the shrimp as food.
Provided you got both male and female cherry shrimp (females are generally bigger than the males and more colourful unless you have high grade fire reds), then the shrimp will more than likely breed. Because Cherry shrimp are basically bottom of the food chain they tend to have lots of babies frequently and provided some shrimplets can avoid predation your numbers will increase. Thick plants and structure the fish cant get into will also help protect the shrimp.
Just watch out that the shrimp don't actually make it into your filter. They will be fine in there even very happy with all the easy pickings, but it makes it tricky to clean the filter when you have to watch out for sneaky shrimp.
So far in both HOB and canister filters I have ended up with shrimp, Bristlenose fry, and Cory fry all happily slumming it in the filter.