water change

hi all i have a 125gallon tank with a 20gallon sump, how many gallons would be a good water change bi-weekly any help on this subject would be most appreciated thanks

steve;D

 

10-15 % is always a good target - keep in mind you might have displacement if you have live rock.

 

I usually do 10% to 15%, but there may be some differing opinions.

 

I normally go by eye as far as percentage.

It's not a hard and fast science in anycase.

10-15%

 

Bi-weekly I would do 15-20% personally.

Sorry this is off topic a bit but that's a pretty small sump for a 125, make sure you have enough room in the sump if your return pump goes off that you can accomodate all of the water that will siphon back down to the sump or you'll have some spillage if your power goes out.

 

thats an excellent observation screwtape. ive got a 90 with a 30 sump, and i know at least a good 5 gals or more drains from my overflow.

 

cheers screwtape im getting a new sump very soon, prob about 40gals or somet

 

the actual size of the sump im getting soon is 39" x 18" x 17" wat u think, think that works out to abt 43Gals or somet

 

that should work well steve. but dont keep it filled to the upper marker on it. half way should be good

 

ok cheers divott much appreciated

steve