Could I add more BBG's in the tank? say another 4-5 and could I put a pair of orange chromides in there as well.
BBGs pretty well mix with anything non-predatory. Orange chromides and BBGs usually work well. Your main problem is making sure the BBGs get enough to eat. Don't underestimate this. To some degree you will end up having to overfeed the tank to ensure the BBGs get enough, since the puffers for example are very greedy, but this in turn compromises water quality. So have a feeding strategy in mind: what types of food, how will get them to where the BBGs are, how will you remove uneaten food, how will you maintain good water quality, etc.
I understand that puffers can be tempermental at the best of times but at the moment they all get along very well with no fighting that I have witnessed.
To some degree puffers do vary. Quite possibly this has something to do with the sex of the fish involved, but since we don't know how to sex puffers (usually) this is difficult to use on a practical basis. Of course, it needn't be the male that is most aggressive (female kribs, for example, are more aggressive than the males) but it is probable that males are more territorial since they alone guard the eggs. Be that as it may, there's no way to *guarantee* puffers will work in any given community. The best you can do is provide lots of cover for the slower fishes (plants, caves, etc.) and only add fast or semi-aggressive fishes in midwater that will escape or bite back if the figure-8s overstep the mark. Chromides generally work well.
I need to get a new external filter as well I was looking at the Eheim classic 2215 or the Rena XP3 anyone have any opinions on these or others?
Doesn't matter. The built-in filters in the Jewel tanks are extremely good in terms of biological filtration. Because they are in the tank, a very small pump can shift a lot of water through a lot of filter media. (A canister filter under the tank needs a bigger pump because its working against gravity.) Where the Jewel filters a poor is removing solid wastes. At best, you're using an essentially disposable floss mat to catch detritus, but because the filter is a low pressure design, not much solid waste actually gets suck up from the substrate into the filter. It's mostly floating stuff like dead plant leaves. Anyway, using a filter dedicated to mechanical filtration is the ideal supplement. Either of the filters you suggest would be ideal. What you're looking for is water turnover around 4-8 times per hour in a brackish water tank. So choose the supplementary filter with this in mind and according to your personal preferences and budget. Eheim may well be the best, but Rena has a good reputation too.
I would like to use sand as the substrate instead of gravel that I use at the moment, is childrens playpit sand OK?
So long as the sand is "smooth" not "sharp" anything will do in a brackish tank. I personally recommend silver/silica sand because its chemically neutral. I prefer to adjust water chemistry by adding stuff to the filter, which is more controllable and easier to change. River sand or any other sand with a lime component will buffer the water and raise the pH, but not in a controlled way and only until the stuff is covered in algae and bacteria.
Any help you guys can give is much appreciated
Hope this helps. Cheers, neale
