RCS

[IHaveAquariums]

So I have a 10 gallon RCS breeder tank that's been cycled for a while (I used established media to cycle it and I test weekly) and it had maybe 17~ I bought. I'm now down to 5 or 6, no detectable ammonia or nitrite and nitrate is maybe 5 and the temp is 78°. The tank has big moss balls and hornwort along with driftwood and I feed sparingly when I do using sinking pellets that get removed. However the pH here is about 8, both API tests and city reports have it between 7.8-8.2. I haven't seen any signs of breeding and they just seem to die. Any ideas on why they keep dying? I get them from across the street so same water and a place about 40 mins away and acclimate them. Thanks!

[TMaier]

I lost all of my shrimp when I changed my substrate. I had problems with Black Diamond Sand so I changed to Tahitian Moon Sand. Not just shrimp died. Snails died too. Heavy metals in the substrate. Take a rare earth magnet and see if your substrate moves.

https://youtu.be/tiU9qsxPhe4

[libertybelle]

Mine slowly disappeared when I let the substrate get too dirty. I never tested positive for ammonia/nitrite or had too high of nitrates but they still slowly died off over time and I never came up with a better explanation then that the dirty substrate was making them susceptible to something ...Since I started cleaning the substrate in sections again they’re doing better.

I also think they seem to have a breeding season. Even when they have a light and heater they somehow seem to know when it’s the dead of winter and just don’t breed as much.

The other possibility is that if you’re buying them fully grown from the store they’re already relatively old for shrimp. They just don’t have much breeding/life left in them? When I bought some from a local fish store fullly grown they had a couple of batches of babies and then died off but the babies did well.

[TMaier]

I had over 70 shrimp of all ages. I had started with 10 5 months prior. My tank was stable with 0 Ammonia and Nitrites and 20-40 Nitrates. And then the snails died. I started doing daily observations and found the symptoms they exhibited as heavy metal poisoning. Since I removed the Tahitian Moon Sand I haven’t lost any live stock. I just added shrimp back this week and they seem to be doing ok.

[libertybelle]

Heavy metals will do that. My substrate didn’t have any so that never explained my problem. I think the point is, it could be a lot of things. Like tmaier’s experience if your gravel or sand has any heavy metals or if any of your ornaments do that could cause a problem. It’s really hard to tell with shrimp. Red cherry shrimp can be very hardy as shrimp go but they are sensitive to a lot of things too.

Do you use prime in your water? Prime detoxifies heavy metals. Maybe not enough if it’s leaching from substrate but if it’s just a little residual copper from your pipes or something like that it might help.

Do you use any fertilizers that could contain things they don’t like?