I May Have Made An Error With My Substrate...

Hi JWC, plants can grow fine in gravel but generally do better the smaller/finer it is. When you say basic gravel, is it 'pea' gravel? How large are the individual pieces?

If you stick to hardy/easy plants then you should be OK. I have 2-3mm gravel with no soil or anything like that and my plants do pretty well. However, the substrate is very difficult to change once you've got fish in (I've assumed you haven't added any yet?) so if you think you'll come to regret not changing it later on then you'll perhaps be best off tackling it now.

It's definitely trickier but still doable. Given that the gravel change is likely to take quite a while I would put the heater in the bucket to make sure the temperature doesn't drop too much whilst they're out of the tank. At the same time, I would just keep an eye on the temp to make sure it doesn't then go too high as it's been set to operate in your larger tank. It may also be good to run some basic aeration while they're in there, e.g. a small airstone.

The filter will be just as important because keeping it out of water for a period of time could damage or even destroy all of the patient cycling you've done and thereby put the fish at risk once you're back up and running. As such I would also keep this in a bucket of tank water and have it running (if it's an external filter, just keep the inlet and outlet in a bucket and again keep it running). You could perhaps put it in the same bucket as the fish and heater but it depends on the size of the filter and it's flow rate (as you don't want the fish being thrown around in there).

I would also try to keep quite a bit of the tank water in additional buckets if possible.

any recommedations a what substrate to use?

What fish d'you have? If you have a sand substrate then some fish like that to rootle round in, but it can look messy quite quickly. This can be a good thing in a way 'cos it shows you exactly where to clean.

If you go down the sand route then children's play-pit sand is best. It's got rounded grains and of reasonable size so they don't pack down too tightly and aren't sharp for delicate fishy mouth bits - and it's cheap (especially if you knick it from your neighbours!!! No names here, of course  ). Just rinse it before use.

If you go down the sand route then children's play-pit sand is best. It's got rounded grains and of reasonable size so they don't pack down too tightly and aren't sharp for delicate fishy mouth bits - and it's cheap (especially if you knick it from your neighbours!!! No names here, of course  ). Just rinse it before use. - See more at: http://www.thinkfish.co.uk/forum/index.php/topic,1288.msg12594/topicseen.html#msg12594

 
 i would never take someone's sand 

just the soil