Whats wrong with my Clams?

[MarkoD]

But I keep all my perameters in check and I have far more sensitive livestock that's doing just fine. I dose my tank daily

[Flash]

what are you dosing?

[fishytime]

I think that clams are probably one of the most sensitive things that we can put in our tanks.....they are somewhat like a sea squirt.....they filter large amounts of water through themselves in a day....not as much as a sea squirt but still enough that the water quality needs to be excellent.......stability is key.....I dont recommend to any customer to put a clam in their tank until the tank is about a year old.....the first year of a tanks life is usually a very unstable environment.....the excitement of a new tank usually brings a lot of new additions, which in turn causes a perpetual teetering of the balance of the tank.....generally speaking the new additions tend to slow down after a year or so and the tank has a chance to catch up to all the "teetering" and mature......

[MarkoD]

But why all of the sudden? I've had them in there for so long. And I've seen noticeable growth.

I check my perameters with Hanna checkers. I'm certain that phosphates and nitrates are at 0

[MarkoD]

I dose kalk through top off and the separately dose calcium, alk, and mag when necessary

[fishytime]

those aren't the only elements and trace minerals that our critters use .....stuff like strontium, potassium, iodine and a host of others will slowly get used up.....if your not adding these things and not doing regular water changes, then these minerals and elements will never be replenished....

[MarkoD]

So how big of a water change do I need to make an impact. I've got 250 gallons total.

[MarkoD]

actually i just remembered. i did a 10 gallon water change about a week and half ago. few days after i noticed the clams close up. it didnt change anything.

also, this wouldnt really explain why they would open slightly more at night