First water analysis - High Tin

[ReefJCB]

I just got results from my first triton analysts and would love some feedback.
https://www.triton-lab.de/en/showroom/icp-oes/107986
I am running a mixed 125g reef with 40g sump. I've got a skimmer set up and do water changes with reef crystals about every 2 weeks. I recently had a total loss of fish due to low oxygen in the tank (still not 100% sure what caused this) and decided to go fallow for 3 months to be safe.

I am dosing 30 ml of liquid soda ash (home made) throughout the day and stay pretty regularly within the 8.5 - 8.7 (Hanna) dKH range. My tank seems to be using almost no calcium. With how much alk I am dosing, I would expect to need to dose Ca as well. But it is staying elevated (around 470 with salifert test) with just water changes alone.

Looks like my Tin (11 µg/l) is my biggest issue. I know that my nutrients are high as well but I am not worried about that, I have been ghost feeding to keep my bacteria up while fallow.

Any idea what could be causing elevated Tin and how I can rectify it? I've got some rusty screws in my tank stand door that I am going to be replacing and doing an inspection of all pumps, any other ideas?

Also, does high tin sound like it might be the culprit for me not being able to keep berghia nudibranch alive?

 

[Lasse]

I do not think that your tin is your problem. I´m more worried of your salinity - its around 38 psu. Check with help of this tool

https://recifalnews.fr/2017/05/compute-salinity-from-sea-water-macro-elements/
Sincerely Lasse

 

[ReefJCB]

I do not think that your tin is your problem. I´m more worried of your salinity - its around 38 psu. Check with help of this tool

https://recifalnews.fr/2017/05/compute-salinity-from-sea-water-macro-elements/
Sincerely Lasse

Thank you for the info! I calibrate my refractometer pretty frequently with some BRS calibration fluid. My LFS has a Milwaukee salinity checker, I'll take some water in there to calibrate my refractometer more accurately. I'll start doing some smaller water changes with lower salinity water to lower it.

 

[Lasse]

I also calibrate my refractometer often. it means that I often open the bottle. The result - the calibration fluid get stronger. I ended up close to 39 psu

I bought a calibration fluid in a syringer - no evaporation :) So if your calibration fluid is in a bottle - suck it up in some syringes and you will have the same standard all the time:p

Sincerely Lasse