I am buying a 5ft diameter tub which is 2 ft 6 deep, to make a goldfish pond. Would anyone like to give me any advice? I have indoor tanks but have never had an outdoor pond and Im not sure what filter I need.

No, I found that out too.

But they are willing to spawn in escargot shells and have done.

Too late, I already went for caudopunks.

I am reviving my idea for a shell dweller tank. I have just bought 3 of 24" x 12 x 15" tanks second hand and I have got some racking for my bedroom and would like some shell dwellers.

When I looked into this last time, I decided I liked Neolamprologus Caudopunctatus as they were colourful and attractive but this was when I was considering filling a 4 ft tank with them. I still have these in mind, but also have looked into multies, N. brevis, L. ocellatus gold amongst other things. I havent seen any locally but know that Wharf in Nottinghamshire has them in stock and can drive there in about an hour.

I was going to use sand as substrate which i understand is essential, plus escargot shells. I have water which has pH of 7.6 to 8 and is moderately hard.

Can anyone give me an idea which ones would suit my circumstances best, also which are the most attractive, fun to watch etc. I would be grateful for any more advice also.

I have got a couple of internal filters running as spares on my other tanks as well as a pair of air driven sponges so my filtration is ready. Just need the fish.

He has quoted ammonia as NH3 = 0 as far as I can tell.

You can make a sandy "beach" for your corys by making a semi circle at the front of the tank and fencing off the area with appropriately shaped pieces of bogwood. The bogwood separates the sand from the gravel. You can also do this with rocks. I did this and my corys loved it. So much so that I just used sand in my new tank.

Ive had a U3 from new and it is noticeably stronger in its output than the Fluval 2+ I have. I also think its stronger than the ouput of the Fluval 3 I used to have too. This is on the top setting though. I just added some brine shrimp above the outflow and was amazed to see them shift across the tank. I havent got the venturi on as I use a separate airline anyway. This is only a 100 litre tank though.

What kind of a goldfish is he? What size of tank is he in? I am sorry to ask so many questions, dont think Im being rude, but do you have any water test results, particularly pH ammonia, nitrate, nitrite? Behaviour can often relate to water conditions.

Dont introduce a predator. It is unlikely all the guppy fry will survive anyway. The parents and other adults will eat some of the fry unfortunately. Separating males and females is one way to do it, but you have to wait until maturity and by the time you can sex them the females are often already pregnant. Sperm from previous matings can also be saved to fertilise further offspring. I seem to remember you had an older, smaller tank. Maybe if you set that up and got it running for when you have to board a few guppies out, or use it as a growing on tank.

I have to say I havent seen a filter quite like this one, but if it is on the top of the tank, is it one of the trickle or wet and dry type filters? Is the water pumped up to the filter where it trickles on to the sponges and drips through? What did you do with the filter from your old tank?

Rinsing the sponges in water from water change is correct, but I usually dont rinse them all at same time, I try and have a system where I alternate what I rinse, but thats just me!