Help with Chemistry

[Ahetrick74]

I am only a few months in to a marine tank. I inherited a 40 cube with crushed coral, 40 or so lbs of live rock and 1 ocellaris. The tank had not be maintained well for the last year but water quality checked out good.
I did water changes about every 2 weeks and topped off with conditioned tap water in between. All was going well, slowly started to add fish, crabs, and snails. Things were going well until a few days ago. I had a damsel and a number of crabs and snails die off over a 2 day period. My test stips (yes, I know... not the best method). Says everything is fine. So I bought new strips with more readings but I'm not sure whether I should be looking at Alkalinity or Carbonate Hardness. I've attached the list from the bottle.

My readings are:
Alkalinity 120 mg/L
Ph 8.0
Total hardness 300 mg/L
Carbonate hardness 20 mg/L
Free chlorine 0
Nitrate 0
Nitrites 0 -. 25
Mercury 0
Lead 0
Iron 0
Manganese .1 mg/L
Copper 0
Zinc 0
Fluoride 1

 

[motortrendz]

Test for amonia.

 

[Ahetrick74]

Sorry, I did with a seperate test for amonia. It is in the 0 - .2 range.
Also phosphate test is at 1.

 

[Ahetrick74]

Also, tank contains 1 ocellaris, 1 greenspotted dragonette, 1 small dottyback, 1 anemone which the edges are looking really bad on, crabs and snails.

 

[Ahetrick74]

Salinity is 1.024
Temp is 79
Anything I'm missing?

 

[Ahetrick74]

It appears as though the carbonate hardness is low but my Ph seems to be stable. Always the same. Do I need to add something to bring the carbonate hardness up?

 

[BeejReef]

A lot of variables.

You have to suspect your water source as a possibility. I don't know about flouride, but there are other possible contaminants not often tested for.

How much are you feeding? Is there algae and such for the CUC to eat?

People often talk about sick anenomes causing massive die offs in tanks. I have no idea if this is true, but you hear about it enough that it's worth a mention.

 

[Ahetrick74]

I feed twice a day, there is some algae and I supplement with tablets and dried seaweed.
The anemone is the newest addition but looked fine for a few days.

 

[TexasReefer82]

You mention that you use conditioned tap water - I'd get yourself an RODI unit if you're going to be in the hobby long term, especially if you want corals. I don't know where you live or what the quality of the tap water is but there can be all sorts of things even in municipal tap water that are bad for marine life besides chlorine and chloramine.

 

[Ahetrick74]

You mention that you use conditioned tap water - I'd get yourself an RODI unit if you're going to be in the hobby long term, especially if you want corals. I don't know where you live or what the quality of the tap water is but there can be all sorts of things even in municipal tap water that are bad for marine life besides chlorine and chloramine.

I totally understand that and I will eventually. My 'tap water' is essentially rain water, I am in a very rural area. As you can see, no chlorine or flouride etc. are added.

 

[lapin]

Welcome
Do you have a well or do you have rain water collection?
If it is a well did you have it tested when drilled? There can be things like arsenic ect..
www.rclabs.com/common-drinking-water-contaminants/
These can build up over time.
Was the tank running on the same sort of water before you inherited it?
The nem might not like the new tank water, light, flow. What sort of nem is it?

 

[Ahetrick74]

Welcome
Do you have a well or do you have rain water collection?
If it is a well did you have it tested when drilled? There can be things like arsenic ect..
www.rclabs.com/common-drinking-water-contaminants/
These can build up over time.
Was the tank running on the same sort of water before you inherited it?
The nem might not like the new tank water, light, flow. What sort of nem is it?

Technically it's public water but it truly is rain water collected and distributed. The quality is not great so we filter through the water filter on the fridge, but it does pass inspection every year. This water is different than prior to me taking the tank.
The nem is a maxi mini carpet.

I guess I'll move the Ro-di up on the list of things to get. Otherwise, do the other levels look right?

 

[lapin]

The nem should be placed on the rocks with good strong lighting and quite a bit of flow. It will move if it does not like where you put it.
Your alk is a bit low . I figure it to be 120/50= 2.4meq/l= 6.72dkh This could explain the nem problem if it was used to higher levels. I would try to get it up to around 7.5 to 8 dkh.
A phosphate level of 1 is way to high. It should be around .1ppm
Im not really sure why you had things die.