No Luck With Inverts - Please Advise.

I woke up this morning and my golden asian clam was floating. I picked it up and noticed that it was not fully closed and it wouldn't close upon handling and it smelled bad - obviously dead. I bought it a few days ago from a lfs (not as local as I'd like) and it hasn't moved much in the tank. All parameters are: ph 7, nitrate and nitrites are 0, kh is 180ppm and gh is 120ppm. The water usually isn't this hard, it is due to the addition of Epsom salt, which I won't be doing again.
My tank has a turnover of about 10x an hour, has co2 (1.5 bubbles/sec), I dose with seachem products - nitrogen, phosphate, potassium, excel, trace, and iron (complicated schedule and only partial doses). The tank is heavily planted.

I am upset that it died, I was looking forward to having such a different form of life in comparison to the fish. I'm trying to figure out what could have caused this. It has never moved in the tank. I've noticed it open slightly and close if I came by or tapped on him to see if he was alive on day 3. On day 3 I added the Epsom salt, which is what caused the high kh and gh, I saw no change in behavior since then and was quite surprised to find it floating this morning. I will note that I've also struggled with shrimp. I bought two Amanos at the same time (and place) as the clam and both of them were dead within 30 hours. All my chems are safe and there is some (though very little) algae for them to eat. Is my water to clean or my turn over too low?

 

What is your ammonia level? Do you shut your Co2 off at night?

 

I guess I've assumed that the ammonia was at 0 since the nitrates and nitrites were as well. the tank is 2 months old and has had fish in it for just as long. Is it worth it to buy a test specifically for ammonia and if so do you have any recommendations?

 

I guess I've assumed that the ammonia was at 0 since the nitrates and nitrites were as well. the tank is 2 months old and has had fish in it for just as long. Is it worth it to buy a test specifically for ammonia and if so do you have any recommendations?

Inverts are very sensitive, so it is always worth testing ammonia. I use the API liquid test kit. That's not necessirily the problem (especially if your fish aren't showing any signs of distress) but it can't be ruled out without testing.

The other issue that is a problem for inverts, but not usually fish, is copper. Do you know if you have high levels of copper in your water?

 

I know that I'm not adding any through the ferts but it never occured to be that it could be in the water I'm using to fill the tank. I'll get a test kit for that as well. Thanks for the suggestions!

 

I know that I'm not adding any through the ferts but it never occured to be that it could be in the water I'm using to fill the tank. I'll get a test kit for that as well. Thanks for the suggestions!

There are test kits, but before investing in a copper test kit, I would use google to see if there is any information from your local municipality about the tap water. I think most US cities publish that data. If it turns out you have copper in your tap water, then you might need to consider RO water if you plan to keep inverts.

 

Sometimes unless specified. Copper is in the ferts as well and can build up over time. They have invert safe ferts too. But I agree with seeing if it's in your water.

 

So.... I got the test kit and tested yesterday, both for ammonia and for copper. I have 0ppm for both. I'm really frustrated and have no idea what is causing the problem. Prior to the clam dying I had ordered 3 amanos (I had figured the first two were a fluke). Today the last of them died. Its been close to 72 hours since they were introduced to the tank. I'm really stressed, inverts are really interesting as their behavior is so incredibly different from that of the fish. I want to fix whatever the problem is so I can add these intriguing creatures to my tank. Does anyone have any other suggestions?

 

On day 3 I added the Epsom salt,

Do you remember how much you added? Epsom salt, being MgSO4.7H2O, increases GH (but not KH). It generally isn't a good idea to subject any aquatic fauna to sudden fluctuations in either as it impede their osmoregulatory process (this is why we acclimate).

 

I added 4 tbsp to 15 gallons. I had read 1tbsp/gallon on two sites but this seemed quite high. I opted to no longer use this method. Since then I have done 3 20% water changes and helped drop that back down. Gh is now about 30ppm

Okay, so in my frustration I completely overlooked the fact that I have success with SOME inverts, I have 14 mts and a nerite snail as well. All of which I've had for some time and are doing quite well. Does this rule out any issue with my tank and suggest shrimp and clam that were already in poor health?

 

In an established tank, you should not be seeing Nitrates at 0. They are the end product of the cycle and should be present. With inverts, they shouldn't be allowed to go much over 10ppm. I can't say why the shrimp died but clams are filter feeders and much more difficult to keep alive.

 

In an established tank, you should not be seeing Nitrates at 0. They are the end product of the cycle and should be present.

Unless they’re being absorbed by the plants in a heavily planted tank—which OP does.

 

I added 4 tbsp to 15 gallons.

That's a very extreme change in GH: about an increase in 22 German degrees of General Hardness (dGH) or 409 ppm CaCO3.

I think this is the most likely candidate for your shrimp (and perhaps your clam) death: changes in GH (as well as KH) have to be done so progressively - something on the order of half a degree per day - in order to limit the risk of osmotic shock.

Regarding the toxicity of nitrate and copper in ferts to inverts, I'll quote a post I had made in another thread that has some links to Tom Barr (the developer of EI dosing) and his thoughts:

There's a lot of misconceptions around nitrate and copper toxicity in ferts from newer planted tank aquarists. Tom Barr, the developer of Estimative Index and a noted American planted tank expert, routinely breeds shrimp in planted tanks where he doses excess nitrate. This is one post of Tom's at planted tank where he challenges the idea that excess nitrate within the EI method (to which Thrive structures its dosing recommendations) has an effect on shrimp.

Likewise, people often believe that the minute amounts of copper in ferts is somehow responsible for copper toxicity in shrimp. This is another post of Tom's at planted tank where he challenges the idea that the tiny amounts of copper in ferts is toxic to shrimp.

There's a lot of ways to kill fish/inverts/plants, but excess nitrate and copper from ferts is rarely (if ever) one of them.

In an established tank, you should not be seeing at 0.

They're likely 0 because the tank is heavily planted.

 

Thanks Minnowette. I'm going to give them another shot. Clam first, and see how it holds up.

 

is this a salt water, brackish, or fresh water tank setup?

 

Freshwater.

 

oh ok, so you had a freshwater clam in your tank. Um, I know not much about freshwater clams.

 

Correct, it was a Golden Asian clam

 

That does sound like a lot of epsom salt. I'd be cautious about even adding 1 tbsp to 15g.
Make sure you get your measurements right because 3 tsp = 1tbsp.
I would start with shrimp before the clam