My PH is still very high

[Marion]

Our tank is now almost 4 months old. I t has cycled & now the algae is
gone, the water is finally clear. But we have a PH problem. The Ph stays
around 7.8. I have added PH regulator, PH down, water softenor pillow in
the filter. You name I think we have tried it. We have well water & it is
hard, with a softener system. The ph is about 6 when it goes into the
tank but then it shoots right back up. There is no coral in the tank. We have
done water changes using bottled water again ph is 6 when then water
goes in & then shoots back up. We have lost some fish but nothing
major. Help! We want to get more fish but need to get the PH down. We
presently have:3 head & tail lights, 7 silver tetras, 1 mail guppy, 1 chinese
algae eater, 2 sunburst platies & 3 zebra danios.

 

[Slappy*McFish]

I wouldn't fight it, but instead work with it by stocking fish that prefer a higher pH....the only fish you have that will not like a high pH, are your tetras.

 

[RENEGADE]

ditto. my tetras didn't like 7.8 but my chinese algae eater does! and this trasparnt(sp?) one but i don't know what its called.

 

[Faramir]

7.8 is not high. 8.5 is high.

I suspect you have a fairly high KH. This resists changes to the pH. I'd just leave it be; I can't think of any common aquarium fish that will suffer at pH 7.8.

 

[Marion]

Originally posted by Faramir
7.8 is not high. 8.5 is high.

I suspect you have a fairly high KH. This resists changes to the pH. I'd just leave it be; I can't think of any common aquarium fish that will suffer at pH 7.8.

How do I get this PH down so we can add fish that don't like such a high
PH ? Is there something that can be done & why does it go up ?

 

[Faramir]

It goes back up because your KH is high. I would suggest you don't try to lower it unless you are going to try breeding tetras or Apistos.

If you feel you must lower it, then peat filtration is probably the way to go. But depending upon the actual value of the KH, it may take quite a lot of doing.

 

[JSchmidt]

Your water resists changes in pH because of the buffering capacity it has, represented by the carbonate hardness (KH). The buffering resists changes by taking up acids that might otherwise drive down pH.

Your efforts to date to lower pH have been unsuccessful because the buffer helps pH to rebound. You add some acid, it looks to work, but then the buffer takes it up and your pH bounces back up. Some neutral regulators (e.g., Proper pH) add phosphates to soften the water (i.e., neutralize the buffer), but if KH is high at all, you have to add so much that you're likely to get algae blooms, foaming water, etc. Plus, everytime you do a water change, you replenish the buffer and have to start all over again. For this reason, most experience aquarists will advise you that trying to control pH thru additives is a losing battle, and the resulting yo-yoing of your pH will be quite hard on your fish.

If you must lower pH (and I'm not sure you do), you could invest in reverse osmosis equipment, which strips water of all these other components and allows you to reconstitute it to the pH and hardness you desire. Not for the inexperienced or faint of heart.

Most likely, the fish you seek to keep will do fine in your tap water. I keep angelfish, tetras and lots of other softwater, low pH preferring fish in my 7.8 water. What fish do you want to keep?

Jim

P.S. Note that many pet store employees will try to convince you that you must keep pH at 7.0. Also note that they generally have a multitude of preparations to sell you to try to accomplish this. Further note that they generally don't use this stuff themselves on their store tanks...