The Puffer Forum

Ok I have read the brackish tank information on here and on the web regarding turning the tank from fresh water to brackish. I understand about .002 per week but the maths bit is killing me.

I have a 15 gal tank and will be changing 20lts per week using 2 10ltr buckets which i will mix up the night before etc.......

What i dont understand is do the buckets go up .002 each week or do i need to add more salt to the buckets which will then mix with whats left in the tank.

sorry if i sound dumb lol

Garry

so is the below correct?

if my tank is now reading 1.002, next week i remove 25% then the 25% i put back would be 1.008?

I'm terrible at math! Did you read that thread?

lol your as bad as me, i did read the link but not sure if i have the maths correct, i did do the easy thing today and start it of by reaching 1.002, well just under anyway.

sorted, the penny has just dropped,

There is a chart in there showing what SG needs to be mixed with what SG to get the Desired SG. If you are doing 25% changes double the SG on the new water you mix. So per the chart if you are going from 1.002 to 1.004 the water you need to mix for your water change is 1.006 (if you're doing 50% changes). Seeing as you are doing 25% changes you need to mix your water to 1.012.

I highly suggest against doing water changes less than 50% when you're raising the SG due to the possibility the higher SG getting pulled in to your filter or killing off bacteria on surfaces in the tank. It's not a huge issue but an issue none the less that could cause possible ammonia spikes due to a small die off. When you add the higher concentration SG make sure you add it slowly. Why only 25%? It takes the same amount of salt to make 40 gallons 1.004 as it does to make 20 gallons 1.008.....

I will go for a weekly 50% change