need help

[kga943]

hi new to forum i have a question about my 45 gal salt tank,i have 1 blue damsel and 1 star fish in the tank and when i try to add more damsels they only live for 3 or 4 days what could be wrong my salt level was around 1.25 i lowered it to 1.20 so was that enough to kill the new damsels,all other levels seem good i have live rock and live sand in the tank and use a ecosystem algae filter with miracle mud tank has been running for 6 months now

[Northernguy]

Welcome to the Fabulous AC!:22:
Hopefully someone will be along shortly to give you some ideas.

[Oscar_freak12321]

Welcome to the forum! Sorry, but I know squat when it comes to saltwater. :14:

[MCHRKiller]

1.020 is a very low SG level, it could be a bit of a swing for new fish to acclimate to...so yes it could have led to their death by causing stress. But why did you lower the SG to such a low level?

[labnjab]

How much live rock and sand do you have? Are you using a skimmer? How fast did you drop it to 1.020?

[kga943]

hi i have around 15lbs of live rock and 30lbs of live sand and i dropped my salt level down with just the 1 damsel and star fish in it over a couple weak time span it was up at 1.25 and i have heard that can cause problems for fish thanks

[labnjab]

1.025 is what you want to aim for for a sg, its close to natural sea water. A drop that large in 2 weeks is way to quick. I started out with a sg of 1.022 and over the course of several months raised it to 1.025. 15 lbs of live rock is not nearly for filtration in a 45 gallon, I would recommend a total of no less then 45 lbs, preferably 60 or more. You are probably getting a large ammonia spike when you add more fish due to the lack of live rock and that is probably what is killing them. I have over 50lbs in one of my 29 gallon reefs.

[kga943]

ok what about the ecosystem algae filter does that help any and why do you think the 1 damsel and starfish keep living

[labnjab]

All that is going to do is help reduce nitrate and phosphate, keep ph stable and control unwanted algae growth , Its not really a bio-filter. In a saltwater system, there is no good substitute for live rock filtration, but since you already have fish, I would get the remaining rock as dry rock and it will turn into live rock over the course of a few weeks, or you may cause another cycle and kill the rest of the fish if you add another 30 or more lbs of live rock. I would also make sure to have 1 or 2 decent powerheads for circulation if you don't already have them

You current rock may be just enough filtration to support the starfish and damsel you have, and that's why they are surviving, but with only 15 lbs of rock its like running a filter rated for a 10 gallon tank on a 100 gallon tank if you know what I mean

[sid101]

Regardles of your water treatment and parameters wich have already been looked at i would like to advise you to check the damsel you already have in the aquarium and it's behavior, damsels are great fish to put in a new tank but are extremelly agresive against anything new you put in the tank and that can be a part of the problem you are having, even is damsels are very hardly and a bautiful should be add as the last fish in the aquarium due to it's agresivenes and territorial behavior.

Since you already have one damsel and you are not going to get rid of it i would advice you to rearrange the rock work everytime you add a new fish in that way you change the established territories in the aquarium and the damsels agression can be controled a bit by that.

Good luck with your tank =)