Maintaining SG

[Pufferpunk]

Try a cup & see where that gets your SG.

 

[Silver Surfer]

50% every 3 weeks can cause shock to your fish.

I've been doing this for almost 2 years now on the brackish tank with zero problems...... what is your reasoning behind this?

 

[cdawson]

I've been doing this for almost 2 years now on the brackish tank with zero problems...... what is your reasoning behind this?

It can cause osmotic shock to the fish, I would cease to continue doing that. You've been lucky so far, think about it. You're allowing the nitrates to shoot through the room in that time and then you're causing them to shoot down. Extreme changes in water chemistry are BAD.

 

[cdawson]

I do a 50% water change every 3 weeks in my 36 gallon..... Use a hydrometer and slowly add salt until you get to the SG you want. I usually end up checking my hydrometer 2 or three times until I get it right. As long as its betewwn 1.008 and 1.010 I'm ok. The smaller the tank is the harder it is to be constant because less salt is needed to make a bigger change.....

Are you adding SALT to the tank?

 

[Silver Surfer]

Are you adding SALT to the tank?

After the water change I add the proper amount of salt to get back up to the proper SG, 1.008 to 1.010 All the bacteria built up on the media in my 2 canister filters and my fairly large bio-wheel as well as the rest of the equarium decorations etc should be enough to prevent a serious nitrate spike? right?

Explain this further.....

 

[cdawson]

no, because a large enough change in water chemistry will kill off enough of the bio-bed to create an ammonia spike. Then a mini-cycle will happen and possibly a bacteria bloom. If this has not happened to you yet you're lucky.

If you're adding salt directly to the tank you're also lucky to have not lost any fish. Direct contact with the salt will burn your fish, if they eat it you have even bigger problems.