[quote="thgng]Yes, there are. I suspect that the birth of the baby shrimps has somehow
used up all the Calcium.. Is that possible ?[/quote]
As long as there are coral chips, they will continue to release CaCO3. However, they do so rather slowly. Do you have plants in the aquarium? If so, are they showing any signs of calcium deficiency? It might be that the plants are absorbing the Ca as fast as it is released.
I think it is those we buy from the drugs store. It says "Calcium Carbonate 500mg". I'm not too sure if there are additive added.
How much should I dose ? Does anyone here actually uses these pills ? Is it safe ?
If they are dietary suppliments, they probably have some dextrose in them. Not really a big deal -- but it could encourage bacterial growth. The only concern I would have is if there is some preservative or artificial coloring/flavor.
As for dosing, I would do it as part of a water change -- add the CaCO3 to the water before adding the water to the tank.
How much to dose depends on your desired KH and GH. Since we are not dealing with a highly sensitive chemical experiement, we can be a little sloppy in the calculations.
1 degree KH ~= 18 ppm CO3. So, to reach a KH of 5, you need 5*18 = 90 ppm CO3. For simplicity, we can take 1mg per Liter as 1ppm. Thus, 90mg per liter will give us a KH of about 5. 1 gallon is, very roughly, 4L. So, to give 1 gallon of your water (0KH) a KH of 5, we would have to add 4*90=360mg of CO3 to the gallon of water. By mass, CaCO3 is 60% CO3. So, we would have to add 360/.60=600mg of CaCO3 to 1 gallon of your water to get a KH of 5.
Note that the CaCO3 will also raise your GH. 600mg of CaCO3 per gallon of water will raise your GH by about 60ppm (a bit more than 3 degrees).
I fed my shrimps twice a days.. is that the cause ?
Any advice ?
Could be. I feed mine about once a week. The rest of the time, they eat decaying plant material and micros.
