Decline in specific gravity

saltwatervirgin

saltwatervirgin

Member
My 75 gallon tank is going into the 2nd week of cycling. I have 28lbs of cured Figi LR so far and plan to add an additional 50lbs today. Currenlty, I do not have damsels and after reading many of the posts on this message board, I may not add them. However, when I checked my specific gravity last night, it decreased from 1.025 to barely 1.020. I did did a partial, and I mean partial (3 gallons) water change last night in an attempt to increase the specific gravity. (I only had 3 gallons of aged saltwater on hand).
Could someone please tell me why my specific gravity decreased over a week's time? This morning the specific gravity was at 1.022 but I would though it should be higher. The temperature in my tank remains at 78 F.
I plan on adding 50 lbs of Figi (pre-cured) LR today. Is this specific gravity acceptable for cycling? Should I do a water change in a few days?
I would really appreciate the assistance in this matter. :rolleyes:
 
col

col

Active Member
I wouldn't worry about it too much until cycle is complete. Don't change any more water until after cycle.
What are you using to test SG, it may be faulty or innacurate.
 
beaslbob

beaslbob

Well-Known Member
just wanted to second the don't worry until cycle is complete. While most people do water changes, all i ever do is replace water which evaporates. I recommend you do that at least until cycle completes.
After 3 weeks or so you may want to try a (or few) mollies. They are very inexpensive, peaceful, and very hardy.
 
hookedonreefs

hookedonreefs

Member
I agree with both preious posts. At this point don't do water changes. It will only lengthen your cycle.
As far as SG goes look into two things. 1) (echoing what col said) what are you using to gague SG. 2) Do you have alot of salt creep. My tank dropped signifigantly (for 1.025 to 1.022) in a two month period. This was due to salt creep. Now I just keep a vigilant eye on things and top off with saltwater when needed to boost the AG a little.
Again, don't worry so much during the cycle. The cycle is kinda the "calm before the storm". We all know something interesting is going to happen soon and we all get anxious. Then, we get too busy with our tanks, and before you know it lots of your free time is going into the tank. Sooooooooo, enjoy the calm for now, in a month or two you'll be pulling out your hair over algae, Ca, Ka, pH and anything else you could not imagine would go wrong.
Have Fun! & Best of luck.
 
col

col

Active Member
What type of hydrometer?
Just in case it is faulty can you verify it against another one?
 
You must log in or register to reply here.
Top