Why did my nitrates and alk drop while on vacation? Should I give a extra dose?

[dnprall]

Went on vacation 3/10/23 to 3/18/23. I had an auto feeder for once a day pellets (small amount) and my father was coming every other day to top off the ATO and feed some brine shrimp. No changes in dosing of NeoNitro, NeoPhos, or All-for-Reef. I did increase my light intensity from 50% to 70% prior to leaving (5% increase daily but then didn't change anything while gone).

Got home today. Cyano wasn't nearly as bad as I was worried about but still multiple patches on the rocks and gravel. Lost one hermit crab (don't know what happened but it was out of shell; hopefully the bristle worms will get it tonight). I collected some water for testing, blew off as much cyano as I could see and then did a 5 gallon water change with some gravel vacuuming.

As you can see on the graph, my nitrate decreased to 1.4 and my alk dropped to 6.9.

Things seemed to be quite stable for some a few weeks.

Could the decrease be due to less feeding? I would think that's why the phos dropped but I don't know about the nitrate and alk. I'm thinking that is the cause.

Also, should I give an extra dose of my additives or is better just to get back to my regular feeding schedule and go from there?

Thanks!

 

[MERKEY]

What size is your tank?

 

[dnprall]

What size is your tank?

43 gallons in DT, 53 gallons total system

 

[MERKEY]

How old and do you have any coral or coraline growing?

 

[dnprall]

How old and do you have any coral or coraline growing?

Tank started 12/2/22 with live rock from the LFS (LFS set it all up). I do have coraline on the rocks. I have a bunch of zoas, two colonies of GSP, a torch, a hammer, and a frogspawn that all appear to be happy. I have two clown fish, YWG with pistol shrimp, turbo snail, cleaner shrimp, tiger conch, 2-3 peppermint shrimp, bunch of snails/hermit crabs.

 

[MERKEY]

I'd say the corals and coraline have used the alk and the nitrate drop could definitely be the less feeding.

 

[dnprall]

I'd say the corals and coraline have used the alk and the nitrate drop could definitely be the less feeding.

Thanks. Probably will give the tank a little extra dose.

 

[dnprall]

Thanks. Probably will give the tank a little extra dose.

I’ve been dosing 2 mL of microbacter7 about once every 5-7 days (trying to get good bacteria too our compete cyano) so maybe that’s bringing down the nitrate too.

 

[Auto-pilot]

The only other thing to consider is magnesium. If your magnesium is low your calcium and carbonate will precipitate out of the water. A sudden drop in alk could possibly mean low magnesium, also the increased light might mean increased growth resulting in an increase of calcium and alkalinity intake. Just a thought.

Edit: I see your tests indicate good magnesium. If this problem persists maybe a confirmation of accurate results could help troubleshoot

 

[dwest]

I see this all the time when I travel.

Nitrates get lower for me as I feed less when I’m gone.

Alkalinity usage increase for me because there are fewer people in the home producing carbon dioxide. This means higher tank pH and increased uptake of alkalinity.

I think it’s pretty cool

 

[Randy Holmes-Farley]

I see this all the time when I travel.

Nitrates get lower for me as I feed less when I’m gone.

Alkalinity usage increase for me because there are fewer people in the home producing carbon dioxide. This means higher tank pH and increased uptake of alkalinity.

I think it’s pretty cool

I agree that both of those are likely explanations for what the op observed.

 

[Auto-pilot]

I see this all the time when I travel.

Nitrates get lower for me as I feed less when I’m gone.

Alkalinity usage increase for me because there are fewer people in the home producing carbon dioxide. This means higher tank pH and increased uptake of alkalinity.

I think it’s pretty cool

Hmm that's cool I didn't think about this. Does this mean corals are growing faster

 

[dwest]

Hmm that's cool I didn't think about this. Does this mean corals are growing faster

Yes. Coralline algae as well.

 

[MERKEY]

Hmm that's cool I didn't think about this. Does this mean corals are growing faster

Yes when ph raises coral uptake alk, cal and mag at a faster rate.

So coral and coraline is using the alk lol

As I said in my 1st post