General Tank Questions/Thoughts

[TheGaffer27]

Hello All,

Currently I'm the proud owner of a 29G tank with 5 cherry barbs, 6 tiger barbs and 2 small spotted corys. Basically, things are running fine - but I just have a couple of questions as I'm nervous about one or two things.

Brief history: the tank was originally set up in 1999 with 4 cherry barbs, which surprisingly ended up mating(!) and therefore increasing the tank population to about 14 -- these 5 I mentioned before are the last survivors, all born in late 1999, so they're 3.5 years old. Since then I have for various reasons needed to move twice, which involved breaking down the tank 2 times and resetting it up.

I set up the tank again, without washing the gravel (half of it, that is - the rest I jettisoned), allowing it to cycle pretty quickly again with my barbs in there. That was about 6 weeks ago - early January. Last week I bought the tigers and the cats, and so far everyone is happy -- all eating well, all generally getting along (in the usual barb fashion, by chasing each other).

Here's my questions: my Ph in this tank started around 6.8 and is slowly trending up - now about 7.1. (NYC water pH: 6.6.) Now, in 1999, I was having major pH problems (acidic) and so I used a fistful of crushed coral in the back-of-tank filter AND into the actual gravel to combat this. Worked like a charm, almost too well - my tank eventually went to 7.7.

But thats 4 years ago. Some of that gravel I speak of is still in the water, so there's probably, oh, a handful of coral in there, maybe - but the coral in the back of tank filter is long, long gone and washed out.

So, is this a concern at all? I like having it around neutral. I'm thinking of sticking just to regular water changes of about 20% to try to keep it around neutral (I hate the "ph down" nonsense).

Otherwise, tank is fine. No ammonia present, no nitrites, still very small amt. of nitrates (I may be engaging in filter overkill - back of tank AND an undergravel filter.)

Also, what's everyone's opinion on quarantining? I have another tank, just 2 gallons, that I use as a "moving" tank or a hospital tank, but never just as a quarantine.

The last question, is just more relaxed. Any tips on what other fish to add in there over time? Was figuring in a month or so maybe a few more cats, a school of those dwarf rainbows or zebra danios, and maybe a couple loaches. Any opinions are appreciated.

Anyway -- I know that's a long ramble, but all thoughts appreciated!

[loganj]

I think you must still have some of the crushed coral in there. The usual trend with pH is that, due to the biological activity in the tank, it becomes more acidic. pH is relatively easy to raise and pretty difficult to lower IME. I would think, if your source water is around 6.6, you could safely use a neutral buffer such as PH 7.0 when you do the water changes. It should set your water at 7.0 and pretty much keep it there. I don't normally recommend the stuff, but in your case, I think it would work OK. Since your pH seems to be creeping up though, you might be better off to just try to adjust it with the water changes until all the coral has dissolved. What you don't want is the yo-yo effect where the pH bounces up and down...that's sure to kill some fish. The fish you have mentioned are pretty adaptable where pH is concerned and should be fine in anything from 6.5 to 7.5 as long as it remains constant. I have tiger barbs living happily in 7.6 well water.
I would add a couple more corys to the tank as they do best in groups of at least three. I like the rainbows very much and mine seem to hold their own quite well with the fin nipping barbs. Perhaps a group of 3-4 giant danios? They are also schooling fish and, while not especially colorful, are very active. Maybe a suckermouth such as a peckoltia or ancistrus to help with any algae? Gouramis are neat too. The barbs might leave a gourami alone as they seem to prefer to chase each other. I would, due to the barbs, stay away from anything that has long fins or is slow moving.
Logan J