calcium percipatation ??

[dabnub]

please clarify; when mixing new saltwater for water changes i was told to start with all the fresh water you think you will need so you do not have to add fresh water to a saltwater mix as this can cause calcium percip in the dt. But between water changes i was told the losses were fresh and that i should add only fresh ro water to my tank wont this cause calcium percip in my dt??

 

[dschwartz]

As your tank water evaporates, the liquid is released into the air but the 'salt' content remains in the water. The more evaporation you have to higher concentration your salt becomes in the water. By topping off with freshwater (RO/DI, in my case) you 'dilute' the higher concentrated saltwater back down to the optimal range.
When doing water changes, however, you are removing a specific amount of old saltwater (e.g. 2 gallons) and directly replacing with new saltwater (i.e. 2 gallons)
David.

 

[veni vidi vici]

When doing water changes you are removing old saltwater and adding fresh saltwater.When adding top-off water you are adding just plain ro/di water or pure h20 with no salt.
Calcium precipitation is when your salt water is over saturated with calcium and it can no longer remain in solution form ,it will turn back into solid form. Calcium precipitation has nothing to do with water changes or top off water unless you are adding calcium to either.

 

[bang guy]

Originally Posted by dabnub
http:///forum/post/2967550
add fresh water to a saltwater mix as this can cause calcium percip in the dt.
Who told you that? It's not true.
If you try to mix too much salt in not enough fresh water you can cause Carbonate precipitation but it doesn't happen by just adding more fresh water.

 

[dabnub]

ok so fresh water does not cause calcium to percip, where is my calcium going? I have a 29g biocube set up 10-01-08, added some soft coral at christmas, shrooms have gone crazy like rabbits, yellow polops are spreading, only clam is 1 cleaner. Try to keep ca at 420+-20, test weekly and allways have to add seachem ca, also add strontium and iodine, sometimes 2 caps of ca to achieve 420 is this normal? What is a better way to keep ca up in my tank.

 

[veni vidi vici]

Originally Posted by dabnub
http:///forum/post/2967815
ok so fresh water does not cause calcium to percip, where is my calcium going? I have a 29g biocube set up 10-01-08, added some soft coral at christmas, shrooms have gone crazy like rabbits, yellow polops are spreading, only clam is 1 cleaner. Try to keep ca at 420+-20, test weekly and allways have to add seachem ca, also add strontium and iodine, sometimes 2 caps of ca to achieve 420 is this normal? What is a better way to keep ca up in my tank.
I could be a few things,Your tank could be consuming the calcium,you could have a magnesium imbalance...
You can find some good reading materials on "the relationship between Calcium,Alkalinity ,and Magnesium"Google it and see what you find from Randy Holmes Farley.He has some good info on the web.
You could also look into Kalkwasser ,2 part dosing,or Calcium Reactor ,but i would read as much info on SW tank chemistry as you could digest first and then make some educated decisions.

 

[bang guy]

Originally Posted by dabnub
http:///forum/post/2967815
ok so fresh water does not cause calcium to percip, where is my calcium going? I have a 29g biocube set up 10-01-08, added some soft coral at christmas, shrooms have gone crazy like rabbits, yellow polops are spreading, only clam is 1 cleaner. Try to keep ca at 420+-20, test weekly and allways have to add seachem ca, also add strontium and iodine, sometimes 2 caps of ca to achieve 420 is this normal? What is a better way to keep ca up in my tank.

What is the carbonate level? (Alkalinity)
What softies do you have? Many softies consume Calcium and carbonate very rapidly as they grow.

 

[dabnub]

after reading other threads i checked my new mixed sw, ive been using IO reef crystals, the ca in my replacement was only at 350. not only was i diluting my ca with ro in between change out but also was diluting my ca with my sw mix, no wonder my ca always was testing low. will try seachem reef with my next order.

 

[bang guy]

Reef Crystals should mix up at over 400ppm Calcium. Can you explain, in detail, how you mix up your new saltwater?
Did you test the Alkalinity?

 

[dabnub]

read in another thread where you said that ca & mg dissolve better in cold water. my hydrometer is a swing arm so i have been warming my water to dt temp before adding salt. i do not have a alk test kit yet but it sounds like i need one, also a better hydrometer that is temp corrected. Iuse ro from wal-marts machine and mix to 1.025 agitate with ph for at least 24hr. sometimes if i have left over sw after change i put it in a jug and keep it for up to two weeks. is this a bad habit?

 

[bang guy]

Originally Posted by dabnub
http:///forum/post/2974000
read in another thread where you said that ca & mg dissolve better in cold water. my hydrometer is a swing arm so i have been warming my water to dt temp before adding salt. i do not have a alk test kit yet but it sounds like i need one, also a better hydrometer that is temp corrected. Iuse ro from wal-marts machine and mix to 1.025 agitate with ph for at least 24hr. sometimes if i have left over sw after change i put it in a jug and keep it for up to two weeks. is this a bad habit?
Keeping the leftover water is fine.
When you do the actual mixing the most important thing is the get the Calcium and Carbonate (or Bicabronate) dissolved as fast as possible. If there is a pile of salt at the bottom of the container then Calcium carbonate will begin to precipitate and this would lower the final Calcium level. The indication that this has happened is a fine dusting at the bottom of the container that won't dissolve.
Make sure you add the water to the container first, and yes, it should be cold water.
Pour the salt into the water slowly and stir vigerously as you pour it in so it mixes fast, you don't want any of it to gather on the bottom of the container.
Never pour the water over a pile of salt, it will never mix properly.
A powerhead is good to aerate the salt mix but it's not good enough for the initial mixing, there's just not enough agitation to mix it fast enough unless you're using a huge powerhead.