Sand Hardening in 3-Month-Old Low Bioload Tank with no Corals

[Trenton Henderson]

Hey everyone!

I posted a while back in the reef chemistry forum about issues with what seemed to be calcium carbonate precipitation issues. I wanted to stabilize my levels of calcium and alkalinity, so I began dosing BRS 2 part. The only demand I have is a growing population of coralline algae in the tank. The tank will be a mixed reef, but I need to get the tank matured and get better lights. The tank has two small clowns, a royal gramma, and a skunk cleaner shrimp (plus a few snails and hermits).

Since this discussion, I have found that the calcium carbonate precipitation seems to be a cause of the new tank’s sand bed (both in the tank and refugium). I have seen Randy mention that this often happens with younger tanks or newer sand because it doesn’t have the organic buildup/phosphates to coat the surface before the calcium carbonate does. I am dosing the two parts on a dosing pump directly into a power head over 24 doses (one every hour) a day. My magnesium level is solid at 1350 ppm, alkalinity in the mid-7 dKH range, and calcium quite high for what I want at 450 ppm due to a bit of overdosing to correct the low calcium I previously had.

I would like to have these levels:

Alk: 9 dKH
Ca: 430 ppm
Mg: 1350 ppm

but I just can’t seem to stop the sand bed from soaking it up!

I backed off on the dosing by a good bit and disconnected my CO2 scrubber from my protein skimmer today to drop my pH a bit, so we will see if this helps.

Anyone else had problems with this? If so, how’d you solve it? How long before your tank stopped sand hardening?

As a side note, I had a FOWLR (plus inverts) tank with Fiji pink sand a while back with no dosing and still experienced some sand hardening early in the tank’s life. My current tank is a 60 gallon long (or tall) with a sump. The total volume is somewhere between 75 and 85 gallons. I have two MP40s running on it, so flow is not an issue.

 

[Alex Cataldo]

I would just stop dosing for a while, wait until there is a decent amount of coral and the tank has matured.

 

[brandon429]

we have 0% hardening rate in the sand rinse thread, for eight years running on 350 reef examples, not once.


this sandbed you installed I would assume is unrinsed/that's what the masses do bc it says on the bag no need to rinse

perhaps the high surface area silt we remove in originating rinses is no longer a binder glue in our sandbeds, not sure

you should try rinsing your sandbed the way we do, and if it hardens again and you're not dosing any extra calcium or alk we can feature that as the first event in eight years.


your system can get by on water changes alone for a few assessment months, a new tank isn't requiring calcium and alk dosing just yet. one antlered in $4K in sps might, but not a common reef tank.

 

[brandon429]

*I see this is a 75 gallon tank, our rinse method needs to be done at the start. we can do it while your tank is running, but it's a lot of work on your part and few will agree to it.

Right when you're fed up and hating the reef/do this method. feel free to try any manner of opposite controls before then, but we are at 100% no hardening beds for eight years here as a side effect of making all reefs cloudless, at the start:

Official Sand Rinse and Tank Transfer thread

If you are reading this thread to cure a tank invasion from a link I sent you, we do not need to identify your type of invasion here we do not need you to test anything at anytime regarding nitrate, phosphate etc Above all, we do not need to see a microscope slide picture of your invasion at...

www.reef2reef.com

we do sand rinses on 250 gallon tanks/big jobs in some places there.