First set back

So wake up this morning and 2 out of 4 fish in my tank are dead. Rock beauty and blue chromis. Found them both laying on the bottom of the tank, snails working on them. Blue chromis looked totally white, as if it was bleached.

They were 100% fine last night!!!!

I have all my own test kits and params look good:

Gravity: 1.026
Temp: 78
ALK: 3.2 (8.96)
PH: 8.3
CAL: 400
AM: 0
NO2: 0
NO3: 0..5ppm (varies a lil from test to test)
Mag: 1600


What the heck happened? I am at loss. All coral is nice and open. Everything seems to be doing fine so were those two fish!

Can't help but feel responsible for their demise

 

Some of the things I've done in recent days:

1) Added 4 caps of calcium (One cap is 10mg per 20g) to the water column.
2) Took out filter basket and rinsed out the foam filter, it's been 45 days for sure since it was installed
3) Added a sock with Seachem SeaGel to the skimmer surface box

 

Temp 98! That will do it.

 

That was a typo. I meant 78.

 

Your alk and mag are WAY off. If your calcium is 400, your alk should be 7 to 10. You should never ever add calcium unless your alk is in check. If it is not, you need to dose both at the same time. Also,your magnesium is way way to high. it shouldn't be more than 1450!! Less is fine but that is way to much. I would say alk around 8 and mag btw 1300 and 1450. Did you add the mag yourself? I would also decrease the salinity to 1.023 or 1.024. You said yours was .1026, I am guessing that was a typo.

Do some water changes to get it down asap. After that, get that alkalinity up (also asap)! I would use the same product for the calcium and alkalinity. Dosing both calcium and alkalinity is called "2 part" so you can look it up. I think these are def your problem.
There are reef calculators online for most products.

 

You aren't using tap water by any chance... If you didn't add the magnesium yourself that is where it might be from. That level is dangerously high. If you are using tap, you need to invest in a RODI unit asap, or go buy some RODI for the water change.

 

Fist of all appreciate the advice. Please do not interpret my questions below as not willing to accept it. Just asking to learn:

I have a Red Sea PH and ALK kits. On the ALK chart the ranges are:
0 - 1.6 = Low
1.7-2.8 - Normal
2.9 - 3.6 = High
Are you saing it should be 7 or 10? LFS told me to follow the kit instructions.

The salinity is 1.026 measured with refractrometer and 1.024 measured with hydrometer. I always figured the truth is somewhere in between. Is not 1.026 a very common sea gravity?

I never added magnesium. The test kit I have always reads off the chart that ends at 1550. It usually takes me one more drops than what syringe can hold to get the test kit color to turn. Figured that was about 1700.

I use RODI water from LFS only.


I have been dosing both Cal and ALK per LFS instructions. The said to dose CAL 4 caps a day for 2 days until it reaches 400 or slightly more. Then use 2nd bottle to bring ALK into HIGH range per test kit. Also these Seachem bottles specifically say not to use both at the same time. It says to use CAL bottle first, then ALK bottle few days later.

That is exactly what I been doing and it seems that both are where they need to be per LFS instructions. Not sure how i can get it to 7, this Red Sea test kit does not read anywhere that high.

 

Hi gabbyr
his alk is measured in Milli Equivellents per litre at 3.2
your reffering to DKH - to get from Meq/l to DKH you multiply by 2.8

thus his DKH is 8.96 - which is about right for the calc level

agreed his Mag level is extremely high- and elevated mag levels can cause issues, but having said that people dealing with Bryopsis algae have taken mag levels above that and not lost fish - so its not 100% certain the mag level did kill the fish it may have done, but Im not sure

how did the mag get that high? if you have added more than 100ppm in a day, then you may have shocked the fish by increasing the level to much to quickly?

dont know what killed the fish to be honest

could be an oxygen issue, which is worsened at night due to CO2 build up
oxygen level fell dangerously low and 2 fish suffocated as a result

stray voltage at some levels can kill fish pretty quick but same levels dont affect corals - possibly a faulty piece of equipement ?

how big is the tank
how long has it been set up
how long where those fish in before they died







Steve

 

The tank is 55g. It's about 8..9 weeks old. It cycled pretty quick. All params were in check by the end of 3rd week. Had both algea blooms and everything.

I've added one fish at a time and checked params every 2 days afterwards to make sure nothing spikes. It's been perfect and from what i understand except Mag is still perfect.

Fish were in it for the last 5 weeks. The chromis and rock beauty been there for 3.5 weeks at least.

 

just out of interest
what are the other 2 fish left in the tank?

and mag level - most salt mixes come in well under 1500 (1470 was highest I ever got with Red Sea Coral Pro)

so how has yours reached 1700 ?

Steve