Re: Help - Am I going to poison my fish with the background I built ? (NetMax please read)

"Alan Silver"
<[EMAIL PROTECTED]> wrote
in message news:[EMAIL PROTECTED]
> Hello,
>
> [NOTE - this message covers some of what came out of the thread "How
> many times should I wash out the tank before adding fish ?" currently
> here. I posted this separately as I wanted to get more opinions,
> especially from people who have built backgrounds like mine.]
>
> Some time ago I started a thread "What do I use to stick rocks together
> ?" (see Message-ID: <[EMAIL PROTECTED]>) and
> was advised (mainly by NetMax with the help of some useful links) to
> build a fake rock background out of polystyrene.
>
> Briefly what I did was get some polystyrene ceiling tiles and stick
them
> together to make a sheet big enough for the background. I then cut some
> rocks out of bigger bits of polystyrene and stuck them on the tiles
with
> aquarium-safe silicone. I then painted it with non-toxic water-based
> paints (from Toys-R-Us, 99p for a litre) and gave it two coats of
2-part
> epoxy to seal it.
>
> Well, after working on it for quite some time, I finally finished it
and
> was very pleased. It looks very realistic and has loads of caves for
the
> cichlids to hide. I stuck it in the tank and prepared for the first
> fill.
>
> I filled up the tank for the first time yesterday. To my horror, about
> an hour after filling, I saw what looked like streams of milky
substance
> coming off the background. There were also loads of brown particles
> coming off the background. This continued most of the day. By this
> morning, the brown particles appear to have stopped. There are quite a
> lot on the floor of the tank and on horizontal bits of the background,
> but I don't think any more are coming off. The milky stuff also appears
> to have stopped streaming, but the tank water is very milky.
>
> First, does anyone have any idea what could have caused this ? I am
> pretty certain that the epoxy sealed the paint in all over. I don't
> understand how the brown particles, which look like paint powder, could
> have got off the background. Also, anyone any idea what the white stuff
> is? The epoxy I used was West Systems epoxy and is designed for boats,
> so is definitely waterproof. I found the stuff from someone else in
this
> newsgroup who used it in his tank without any of these sorts of
> problems.
>
> Anyway, I intend to empty the tank tonight, wash the background well to
> remove any more particles, then clean out the gunk from the bottom and
> refill. If the refill remains clear and clean, I will risk some small
> cheap living creature to see if it survives.
>
> I'm a bit desperate here. I realise it's almost impossible for anyone
to
> say clearly what has happened, but I'm just hoping someone may have
some
> ideas. I'm really worried about the idea of putting fish into a tank
> that may contain poisons. On the other hand, the thought of ripping out
> the background upsets me too. I worked very hard on it for quite a long
> time and just don't have the time or heart to make another. I'm not
even
> sure I would get this one out cleanly as I stuck it in well.
>
> Any advice would be very gratefully received. TIA.
>
> --
> Alan Silver
>

Polystyrene is non-toxic.  Properly cured West System's epoxy is
non-toxic.  Your paint might have released some particulates, but it's
probably non-toxic as well.  It appears the paint was not completely
sealed by epoxy (?).  There might have been a bare spot, or some crevices
which were not sealed?  This should not present a real problem.  Unsealed
areas will be prone to loosing their paint due to abrasion from plecos,
but if it's just crevices, then it's not a problem.  If the underside of
the structure was painted and not sealed, then you might have paint
particulates slowly coming off the polystyrene as you get water behind
it.  I imagine this will just get caught into the filter over time (if it
enters the water column).  Another possibility was some voids in the
polystyrene filled with water and released some particulates.

I'd fill the tank and let it soak a couple of days.  I'd then do a 100%
water change and observe the water.  If there were any particulates
bothering you, repeat the water change after a couple of days.  If the
water appears clean, then activate the filtration with some fresh carbon
(which gets thrown away after 3-4 weeks).

I have no bad news regarding my last epoxied polystyrene structure.  It's
been in the tank over a year, fish are fine, plants are growing, the
surface gets a bit of algae which the bushynose then promptly scrapes
off.  I used several layers of epoxy, with sand in the last 2 layers to
give it a texture to match my rockwork.

I'd agree with your assessment to proceed slowly but deliberately, and
introduce a low cost but sensitive creature to do your final test.  When
do we get to see pictures?

NetMax