Need advice - algae and cyno; nitrate 0, phosphate 0.3

[Kathryn Lawson]

All right, everyone... more updates!

 

I swapped out the vinyl tubing for silicone, and did 6 ~30% water changes (12 gallons) over the last two months. Sent off an ICP test last week, and got it back this morning - tin is totally gone!!

 

Phosphates are also down - 0.03 according to Triton, so I'll pull the (3 small) phosphate absorbing cubes from the sump and just continue to monitor/slightly dose nitrate. Algae has receded significantly, which has been really nice. The addition of 5 captive-bred tuxedo urchins definitely helped in this area also, but even before they were added, algae growth rates were decreasing to manageable levels. I've seen a bit of cyano forming down at the sand/glass interface and in a few corners, but it has not been spreading past those lower-flow areas (absolutely nothing like the issues I had previously!), and my remaining corals are doing well, so I'm inclined to just keep an eye on nitrate levels and maybe try to increase flow a bit more.

 

Now for the interesting news... I now apparently have high silicon and lithium levels. Given the reducing tank issues, I'm not terribly inclined to worry about the silicon for now, but I do remember thinking that my DI resin would be due for a swap soon, so I'll take a closer look at it. I did just last week find a magnet that the seal had broken on from a (name-brand) frag rack in my sump while cleaning out the remnants of the algae accumulation there (no CUC down there), so that has now been removed. I have had carbon and Cuprisorb in the system since finding out about the tin, so it's possible it removed most of the metals that leached from it, but left lithium (it's not reported to remove lithium). There is also the distinct possibility that since there are no other metals, the lithium is instead coming from my new salt (Instant Ocean, not reef crystals). I've seen discussions of high lithium levels being "normal" in IO salt, and I'm not aware of any major concerns from elevated levels - anything I should keep watch for? Planning to mix up the salt in my bucket just in case things settled out weirdly, but otherwise just monitor as I slowly try to reintroduce more sensitive livestock (inverts).

 

Thanks for all your input, and I'm so relieved that my tank is heading back in the right direction!!

Link to results: https://www.triton-lab.de/en/showroom/icp-oes/210461

Edited May 22, 2024 by Kathryn Lawson

[Gatortailale]

Nice update, and sounds like your efforts are helping. I switched a few months ago to Fritz salt away from reef crystal and been loving the polyp extension on coral. 

[gws3]

I wouldn't worry about the elevated lithium levels, it's from the salt mix. I've been using Instant Ocean for many years, it's always in the 300's, and I keep tanks packed with SPS.

[ranger]

Add a poly filter an call it a day......the large 60 dollar one has a higher affinity

 for some compounds i beileve.

One bad batch of salt and there she goes.

Amazon has 5packs for 45 or 3packs of the large for 105 next day...simple insurance.

[Kathryn Lawson]

2 hours ago, gws3 said:

I wouldn't worry about the elevated lithium levels, it's from the salt mix. I've been using Instant Ocean for many years, it's always in the 300's, and I keep tanks packed with SPS.

Good to hear first-hand feedback! Have you been able to keep shrimp, clams, etc?

[Kathryn Lawson]

On 5/22/2024 at 10:13 PM, Gatortailale said:

Nice update, and sounds like your efforts are helping. I switched a few months ago to Fritz salt away from reef crystal and been loving the polyp extension on coral. 

Interesting, thanks! I'll keep that in mind if I look more into other salts

[Kathryn Lawson]

1 hour ago, ranger said:

Add a poly filter an call it a day......the large 60 dollar one has a higher affinity

 for some compounds i beileve.

One bad batch of salt and there she goes.

Amazon has 5packs for 45 or 3packs of the large for 105 next day...simple insurance.

Thanks! Unfortunately, it seems polyfilter is not rated for lithium, and because it's not technically a heavy metal it's unlikely to help. However, it seems that due to the extremely high amount of sodium and potassium in saltwater (compared to freshwater, for example), medium levels of lithium still cause minimal issues since usually the issues are caused by lithium replacing Na or K and messing up biological processes. At least, that's what I've been reading. I'll certainly keep polyfilter in mind for metal issues in the future though, thanks!

[ranger]

The ideal is to slowly filter a small amount of water through a chemical filter

 first carbon then a layer of poly filter so any household chems/metals/organics...etc

might be removed before any tank crash.

As you can see large water changes are and should be a last resort.

There is a huge difference for your tank size and what a coral farm should do...

Icp test are not reliable its been shown over and over.

They have a place but you should be wary of them.

I run a very slow flow through a brs dual reactor never do water changes on my

 150 plus 2 40 system.....i use a small amount of poly in my reactors.