Llama

Went to a new LFS and I found a very small plant pot made out of clay (got it for 30 euro-cents so quite happy).

Its basically meant for plants, but it has no decoration or paint or anything, it looks clay-coloured.

If I sink it in the aquarium nothing bad's going to happen right?

Dozey

I’ve seen a lot of aquarium pictures with clay pots so I’d have to say yes. But I might suggest soaking it in used aquarium water for a while just in case it leaches anything. I’m not experienced with clay pots so you might want to hold off for a reply from someone who is.

Llama

Hmm, I'll try leaving it overnight in some aquarium water then, would have cleaned it anyway. Will be a good excuse to try out my new gravel vac (I LOVE the 'whoosh' sound)

Right I umm, put it in aquarium water and it started to make fizzing sounds.

It stopped now

What on earth?

Llama

Allright, update.

Left it in a bucket of water overnight, the water looks ok, don't know what I should test it for, but there's no discoloration or anything else.

Sink it?

ADDED:

Decided to test pH. It returned to me a value of 9 (!!!) I tested the aquarium water again and it gave me a 7.5

I guess now I know what the bubbles were.

I'm going to change the water and leave it overnight again, lets see if its still leaching out reactants.

That said, any advice is appriciated

aquarist48

Terracotta pots should be fine as long as they aren't painted or glazed in any way. I have a terracotta snail and 2 14" terracotta columns. They are porous and collect a LOT of good biological bacteria. I suggest you NOT clean it once it has gone into your tank. Let the algae grow on it as well. Depending on what you're using, you could just flip it or roll it over and the underside will be clean. Too, it will produce bubbles for a while but nothing to worry about. Again a great source for Bio matter to collect.

Llama

Fair enough, I picked it up because it'll make a good cave I think. The fizzing seems to have lowered the pH somewhat, was that normal? (I DID put it in a bucket with 3 l of water, so it'll be unlikely it'll effect my 160l aquarium... but can't be too careful)

aquarist48

I don't think it was the terracotta that caused the pH to lower a bit. pH will fluctuate from time to time anyway. Yes, they make GREAT caves as well and is a great addition to any fresh water tank. I don't have salt tanks but I don't see that it would harm them either.

Llama

If it wasn't the terracotta, what was the fizzing sound? Fizzing usually suggests a reaction has taken place. The irony of it all is that its a PLANT pot, so its meant to get a bit wet anyway.

Anything else you recommend I test? The gravity of the water?

aquarist48

I'd say the fizzing was just the fact that water was getting into all the pores creating the bubbles. I only test ammonia, nitrite, nitrate, pH and salinity. I keep fresh water aquarium salt in my 155g for good measure. I don't go over 1.000 for salinity. I think your terracotta pot will be just fine

Llama

Right, I left the clay thing in well-water for around 5 hours, and the water parameters (including ph and degrees of hardness) remained the same.

I suppose its safe to sink it in...