Yikes...what's happening to my tank?

[supersmile]

OK here it goes.... I noticed my kenya tree was dying so I tested the water and everything was OK except salinity.....it was WAY too high. So I began changing the water (Adding regular water) to get the salinity in check. Turned out a lot of the water was changed. Since then my cleaner shrimp and sally light foot crab have died. Now I noticed my sand is turning reddy brown and so is the live rock. My fish (yellow tang, perc, royal gramma), snails, hermit crabs, urchin, starfish all seem to be doing fine. Any ideas what is going on and what I should do? I am moving at the end of the month so I will be moving my tank as well. I'm hoping everything is OK.

[Der_Iron_Chef]

RO/DI water?

[supersmile]

What is RO/DI Water??? I used tap water as I always do.

[PoonTang]

I would guess that your fish died because you changed the salinity of the water too fast. Now you have added alot of fresh water of unknown quality and introduced algae or shocked the tank so badly that you have started a cyano bloom.

[Der_Iron_Chef]

Yeah, what he said. I'm guessing the rapid change in salinity killed your inverts. As well, tap water contains things that could cause algae blooms (or cyanobacteria).

RO/DI is Reverse Osmosis/Deionization.....a form of filtration most reefers use to filter their water.

[Carrera75]

I highly doubt that tap water killed his fish...I have been using tap water for 9 months and my tank is thriving! When I do a water change, I mix the water and do the water change right away.....I know a lot of people mix the water for a day or even for a few days but I have never done that. So far my tank is looking pretty good. I think there are a lot of thing that happen and are very hard to explain why they happened. Most of the time we guess but we don't really know the real reason why something happened.

[Snappy]

Some inverts like shrimp are sensitive to both quick temp & salinity changes so that is likely what did them in. As far as the algae goes it could be a number of things. How old is the tank? and how big? What do you have for filtration, etc? I would need to know some of this info before taking a stab at the cause.

[DanG]

how did the salinity get so high? What are you using to measure it? A hydrometer or a refractometer?

[supersmile]

What happened was I topped up my tank from evaporation and I added salt water instead of plain water therefore the salinity spiked (I know my mistake). My tank is 40gallons and has been running for atleast 6 months now. Everything was doing awesome til now. I probably should have reduced the salinity gradually rather then all at once. Is the sand turning red/brown due to the algae spike??? Do you think it is just going to take some time for everything to adjust? My tank has a skimmer and filtration in the pump.

[christyf5]

The sand is turning red/brown because it now has algae growing on it probably due to an increase in nutrients caused by the death of critters when you changed the salinity so fast. Ride it out, it will pass.

I would just leave your tank be for a bit and let it recover for a couple of weeks. Always make sure to top off with fresh water, taste it first if you have to (I'm sure you know that by now though :wink:).

[Captainhemo]

Always try and make any water chemistry changes gradually.
When you get a chance , invest in an RO/DI system, it really does make a big difference by starting with PURE water as compared to tap water.