View Full Version : Help needed with Hyalella/gammarus problem

5th Oct 2005, 04:08 AM
I have recently seen a virtual explosion of a small crustacean in my shrimp tanks and I had trouble understanding what species it was. I now realize it is Hyalella azteca or Gammarus roeseli.

I have tried removing visible animals but it seems impossible to get them all out! According to species informaion on the web they rarely eat anything but microscopic plancton and decaying plantmatter ( or an occasional shrimplet?) but they are not very estethicly pleasing in the tanks and I need tips on how to get rid of them. They must have come with the original shrimp I bought from a breeder in Germany because I have a memory of seeing one or two of them when I initally started the tanks... only whish I had removed them when they where in the plastic bags.... I have read that they thrive in Riccia and javamoss so I suppose they would have shown up eventually anyway, since I have bought both Riccia and moss from various sources.

Anyone else have this problem?


5th Oct 2005, 04:01 PM
Depend your tank sizes, get 1-4 small sizes fish like lamp eye in the tank should fix the problem. I having this problem too in my 1.5 feet tank and 4 lampeye do very good job eliminating them.

If you dont remove them, eventually predator micro founa will also present in the tank (eg. hydra etc) too.

16th Oct 2005, 11:34 PM
I have now tried using Sera Snecktol with Cupric Sulfate as the active engredience to fight the scuds. A normal dose had no effect whatsoever, but a double dose killed off about 99% of them. :D

I had removed all the shrimps from the tank but accidentally forgot two bumblebee shrimp. They survived the double dose Snecktol so I am now in doubt concerning the shrimps sensistivity to Copper! :huh:

Since there were still live scuds in the tank I lost my temper :veryangry and emptied the whole bottle of Snecktol in the tank ( resulting in aprox. a quadrupel dose). This killed one of the shrimps but had no effect on the remaining scuds, the remaining scuds must be totaly resistent to Cupric Sulfate. :wall:

The surviving bumblebee was evacuated to another tank and I went about lowering the Ph in the tank to give the scuds a Ph-shock! :evil: With a Ph-test and some Fosforic acid I lowered the Ph fom about 8 to 4,5 in 15 minutes. I could literaly see them dying in front of my eyes. Cruel? maybe, but now I was feeling realy desperate. :freak:

I guess I have to wait a week or two to make sure that no scuds appear again before starting up the tank with shrimps again....


17th Oct 2005, 10:31 AM
I've got a similar issue. At first I was thinking...cool, live snacks. Now they are like maggots all over everything.

Well...the tank they are in was set up with a bad batch of eco-complete. The replacement EC came in and it's time to start over. My plan is to get the shrimp out, keeping them in a 5 gallon bucket with sponge filter and some plants. Then, I'm going to empty the 10g, and really clean it with pure vinegar...and possibly a bit of bleach at some point.

The only thing I'm truly worried about is hitchhikers on the drift wood. I may go without driftwood for a while to keep that from being a possibility.


17th Oct 2005, 12:11 PM
Good idea to skip the wood for a while. After the initial dose of Snecktol almost all surviving scuds probably "burrowed" deep inside crevices in the wood, because I saw several of them on the wood afterwards.

I have left all wood to dry for a couple of weeks, maybe iŽll put it in a bucket of clorine for a week or two...


22nd Jan 2009, 06:19 AM
Bumping the best thread I could find - SCUDS are driving me crazy. They don't hurt anything but breed (and look) like fleas.

The only thing I can do is to suck them out one at a time with a small syphon - I can't remove my live CRS from the tank... anyone else have ideas?

EG, build a scud trap that they swim into but cannot find a way out of???