Backyard Aquaponics
A place to discuss aquaponics

ok 1ppt is 1 gram per liter.. you've got 500gallons x 3.8 liters = 1900 liters
1900 grams = 4lbs 3oz for each system to salt to 1ppt x 2 for 2ppt, or x 3 for 3ppt etc

Thanks, do you do that all at one time or in stages? and afterward do you have to add it again? sorry to ask but just want to make sure I do this right...

when i had some fungus looking stuff, i salted to 3ppt, but have not added any since (that was probably 3 yrs ago)
i dissolved as much as i could in a 5 gallon bucket of ft water, and dumped into my sump.. i think it took 3 or 4 buckets to get all the salt in,, kinda freaked me out how much i used that time..
get pool salt, or water softener (pure salt).. stay away from iodized, or table salt - sometimes an anti caking agent is used that can be harmful to fish
if want to keep the levels, you'll need a salt water refractometer to measure levels

Great thanks, I have pool salt. so far I only added .6 lb to each system another I 'll add another 3Lbs or so each and see how it goes. I'm shooting for the 1ppt for now if I noticed any more funky stuff going on with the fish I'll boost up the ppt to 3ppt. then let it rest....

Btw, tilapia can handle extremely high salinity levels. They are pervasive in the Salton Sea, which has a salinity considerably higher than seawater.

cool thanks, good to know.....

Well it's been about 3 weeks since my first post. I am very amazed at the ability of AP systems to get better. After lowering my stocking density and slowing my feeding down(from 3 times a day everyday to 2 times daily and smaller portions) and salting to about 1ppt, both my systems have rebounded. My fish deaths have stopped for the most part, I did pull a couple of small fish that had no visable signs of sickness but were acting slow and easy to catch, so I felt it best to eliminate them at this point then risk further spreading of whatever I had...Thanks for the help and to all newbies, I have been through a lot of rough times since starting. Don't give -up It will get easier and funner. My advice is to start a small system with small stocking densities and listen to as much advice as you can