Fossils?

[lozronz]

Hey,

I got asked to foster a tank for 6 months while my friend goes to find himself in Cambodia or somewhere,
Its a 30g with a big fat pink 4 year old Danio, a Chinese Sucking loach 3 neon tetra, and 3 emperor tetra ... not really my immediate choice for stocking but... friend in need and all!

He has filled the tank with Gravel and loads of fossils, it looks quite interesting but I was wondering how they might affect the water?

 

[raptorrex]

Hey,

I got asked to foster a tank for 6 months while my friend goes to find himself in Cambodia or somewhere,
Its a 30g with a big fat pink 4 year old Danio, a Chinese Sucking loach 3 neon tetra, and 3 emperor tetra ... not really my immediate choice for stocking but... friend in need and all!

He has filled the tank with Gravel and loads of fossils, it looks quite interesting but I was wondering how they might affect the water?

I guess it would depend on the rock that the fossils were formed in. but i doubt it would have much effect!

 

[nmonks]

Ooh, a question about fossils!

Most fossils are found in limestones of various kinds, so over time they will dissolve and harden the water and raise the pH. Unless you're keeping hardwater fish you probably don't want this to happen. If you are keeping hardwater fish, then just check the fossil has no signs of metallic seams (usually looks like rust) but otherwise treat as you would dead coral or tufa rock.

Fossils in slate (such as graptolites) are normally preserved as some type of iron pyrite, which is potentially toxic. So such fossils shouldn't be put in the tank at all.

Cheers,

Neale

(PhD in palaeontology, no less!)

 

[lozronz]

PhD in palaeontology! Sweet! I have an MA in Art Psychotherapy (Although its a kinda micky mouse MA to have!) So any questions on Jungian doodles give me a bell!

Sorry for the late reply but thanks. The fossils were all collected in Chippenham (wilts) canal, I would take a stab and say slate or sandstone (do you get fossils in sandstone?) rather than limestone, they are mostly ammonites and those squid tube things!

I probably don't want the water getting any harder because its pretty hard here already, so cheers will extricate them.

 

[nmonks]

Fossils in sandstone are pretty rare. It's more likely to be in some sort of limestone or oolite that just seems coarse. Ammonites were in fact my speciality, though Cretaceous rather than Jurassic ones!

Anyway, with that in mind, I suspect it would dissolve slowly, hardening the water, which you don't want.

The squid tube things are belemnites (see below). If you want names on things, don't forget than the NHM in London has a free fossil-identifying service.

Cheers,

Neale