Looking for some guidance on my chemistry

Crosby

New Member
Looking for some help with water chemistry and corals dying back.
30 gallon RSM 130d that’s mostly modified, leds etc. Tank is about 8 years old. Mixed reef, 4 small fish, clean up crew, etc. Last few months frog spawn, torch, candy canes are suffering. Lost several heads of spawn and torch, and the canes are shrinking back to just a cm or so left on each head. In fact find a few cane heads floating as the flesh has come detached from the stony part. Also lost a few colonies of zoos about 4 months ago.
Media is Purigen and phosfiltrum. Dose kalk 1/2tsp per gallon in ATO and 3-5ml Nopox daily.
I don’t dose anything else. My numbers are as follows. Temp 77, salt 1.025, ph 8, calcium 489, alk 3.9, mag 1400, phosphate 0.25, nitrate 4. Have RODI filter for ATO water. TDS = 0.
tank has always had lower ph until about a year ago when I started dosing kalk.
About 2 months ago my 8 year old serpent starfish died after his Arms started falling off. My numbers are more in range now than they have been in years past but yet the tank seems to be doing worse. I’m certainly not an expert and looking for thoughts or suggestions. Thank you in advance.
 

Blue Space

Well-Known Member
Hi there and welcome to RS!

When reading through the parameters most are fine with the exception of the the alkalinity, phosphates, & nitrates.

Your alk is very low and should be kept between 6 -12 dkh. Most folks try to find a happy medium here and stick somewhere in the middle. I keep mine around 8.5. The more stable you can keep that (by means of dosing) the better. The key here is stability. The more stable the Alk, the better color and growth I get.

Your phosphates very high and should be maintained at less than .03 ppm. Your nitrates are high too (should try to maintain .2 ppm ) but only regular testing will tell you if it's trending up or down... At current level of 4 my best guess is that you're trending up.

Recommend doing a large wc (35%-50%) or better yet, 5 - five gallon water changes over the next week (once per day) and then testing again to see where you're at from there. I would also recommend raising your Alk by testing to see where you're at before each daily wc (and after) and raising it slowly over the course of a week. Be sure to follow the directions for whatever product you're using to dose Alk. For instance, I use BRS two part. The instructions warn not to increase alkalinity more that 1.4 dkh per day, so be cautious there.

Here's a link to some great info on parameters - http://www.reefkeeping.com/issues/2004-05/rhf/

Also, the polyp bail-out you described has been seen before where the water quality becomes unbearable for the hammer coral so the fleshy part "bails out" in order to find better living conditions as a last ditch effort to survive. If you save the polyps that have detached you can grow them back out if you provide them good water quality again, so don't toss them out.

Hope this helps!
 
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PSU4ME

JoePa lives on!!!
Staff member
PREMIUM
What kind of salt are you using? Some big water changes with a quality salt should get things turned around for you, just don’t go too quick. Alk swings can be tough in corals.
 

DaveK

Well-Known Member
I agree with the posts by @Blue Space and @PSU4ME. I would also add that you should look around for possible sources of contamination. for example using any spray cleaner or bug spray near the tank or anyone throwing pennies or other forign objects in the tank.
 

Crosby

New Member
Thank you for all your comments.

Blue Space: Sorry for my mistake, I gave my Alk in meg/L which is about 10.9 in dKh. I will work on my NO3 and PO4, I didn't realize that they were that bad until I read the link you sent. Thank you for the help.

PSU4Me: I use Red Sea Coral Pro salt.

Dave K: My tank has a hood, but a few months ago I added a longer air intake line for my skimmer that reached another 12 inches to just outside the hood to hopefully draw in some fresher air. We don't ever use chemicals around the tank, so my only thought would be the occasional pan fried smell from the kitchen about 20 feet away.
 
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