I need a little help and advice :(

I moved my tetras and stuff over to a larger tank in September. It's 37 gallons. It was cycled- when I put them in these were the test results: 0 ammonia, 89.5 GH, 53.7 KH, 0 nitrites, 10 nitrates, 7.2 PH. That's where it pretty much held in the tank I had them in before. The difference in their old tank and the new tank is that the new one has eco-complete for gravel instead of the common kind, a good amount of drift wood, more live plants, and no fluval- just the over hanging filter. Also, it has a large bubble wand instead of a very tiny one. There was also an undergravel filter in both tanks. All the parameters have held steady (except there are slightly LESS nitrates) except the PH, which has been slowly climbing and seems to be wanting to push past the 8.0 mark now. It's been showing in my tetras for a while, they don't look as sleek and healthy as they should, and finally I've started to loose them. Last night I lost 2 of them, the night before that I lost 2 more, and the night before that I lost a ghost catfish- he was stuck to the filter (alive but worn out) when I woke up.


This is slightly old, the rocks that were in there, even though I had the same ones in a tank before and it always had a low PH, were taken out, and there are also more plants now. (Oh, and the driftwood came from Dr. Fosters and Smith so I'm not worried that it was unsafe for use.)

I have an RO unit in my apartment that I can get about 3 gallons of water from in a day, and I don't mind buying stripped bottle water, but how do I (can I even) safely alter the PH? I tried a 25% water change with RO water a few weeks ago- but that was fruitless, all it did was drop to 7.4 and then bounce back up to 8 within two hours. I feel like it probably just caused more stress on the fish.. The water is always tea-stained from the driftwood, I thought that it was supposed to help keep the PH lower... I'm at a loss. So, like I said, I would love any help or advice. Thank you so much!

The driftwood should indeed keep the pH low and not high. There are no rocks in there now? Rising pH is sometimes due to rocks that are leaching. I would always suspect a new substrate if everything else is pretty much the same. The pH may also fluctuate more with tanks with plants. Have you checked to see if the pH is high is different first thing in the morning versus the end of the day? There are pH down solutions which contain acids to lower the pH. It would be better to find out why it's going up. A pH of 8 is fine for many fish but not the ones that like acidic water like your tetras who are obviously suffering from that or something. Your tank looks and sounds fine. I hope you can figure out what's going on.

Thanks so much Robyn. I will test the PH several times during the day for a few days to see if I see a cycle. I lost another fish last night X(

I don't really know what I think about this, but I called a specialty petstore in the next town over and talked to a lady who actually sounded like she could know her stuff. She said they suspected two things. 1) that the city placed chemicals in the water to stabilize it. It comes out the tap at 7.0 but often increases, on it's own, to 8 in the span of a week or a month. I wonder if she's right, I've never tested for anything like that. I don't really want to believe the city would do that either and 2) that they know that the city uses concrete pipes to run the water and when they're new they leach lye (spelling?) into the water for about 3 months. There is a lot of new construction around my home. She said if that was the problem that even ph-down solutions don't work against it- not that I think I'd ever want to use that stuff without knowing the problem (like you said). But I may try to test that theory, in a separate tank, before I do resort to that.

Yeah, I took the rocks out first. I didn't really think it was them, because I had them in a tank before that held steady at 7.2, but it certainly would make the most sense if it was. They've been out for around 3 weeks (maybe? forgot when I removed them) but I did a 25% water change then with tap water, and then the next week the RO water change.

I thought I had seen and heard of people using eco-complete as substrate in discus/tetra tanks, it's says it's safe and doesn't alter PH- (but like I'm always going to believe the word of pet products manufacturers. I had some crushed walnuts substrate almost kill my bearded dragon. "Safe for them" my bootie) It's the first time I've used it so I'm suspecting it more than anything else right now. This is the only tank I've ever had a problem like this in (but I am fairly new to this part of the country, so I can't vouch for the water supply) and I've had a few plants and some driftwood in other aquariums. I'm so frustrated *shurgs* Thank you though, you and your site are always so helpful!

The eco-complete was the substrate you removed or is it still in there?

Tap water or well water often goes up in pH a little bit once aerated because out of the tap, it may have compressed carbon dioxide in it (making carbonic acid which lowers the pH). Tap water is usually low in oxygen too. But, once you aerate the water, it should remain at that pH. Buffers (which a water company might add) should be in effect out of the tap and not later raise the pH. The same would seem to go for any leaching that occurred prior to coming out of your tap. In other words, the pH of fresh, aerated tap water should not later go up. The natural processes of plants and bacteria may change the pH up and down during the day and night. Leaching from rocks and so forth in the tank itself often explain large pH increases from initial tap water pH.