[Leebee]

Hi every one, this is my first question on this forum so go easy on me. I have just shut down my marine tank and I am converting the tank to a planted tank setup. I have just about all my equipment ready except co2 gear, but that won’t be too far off. In the past I have had African Cichlids, but these proved to be a pain because of all the aggression with them. So, it will be a nice peaceful tropical planted tank. First problem is my tap water. It would appear that I have high levels of silicate, and this has been proven with silicate testing. This causes and instant and severe brown algae(diatoms) bloom that recedes to a low, but still irritating low level that never completely goes away. Every water change adds more silicate, so there is always a small amount. To fix this problem I have been using an ro/di filter for some time, and this fixes the problem(although more work). Next problem is PH. My tap water comes out at 9!. After 24 hours this drops to 8.3, but still too high. So I will be using co2 with a ph controller to bring this down to a more normal level. So, here is my big question, when doing a water change, my make up water is going to be 8.3(ro/di with bicarb added for kh), can I just add this water, or do I need to adjust the ph first. I have been unable to find much information on the topic so far, so any help will be appreciated.

Lee.
:icon_idea

 

[CatB]

wait, wait.
your RO/DI filter puts water out with pH at 9?
either your filter is broken or your test kit is wrong
i was under the impression that all RO/DI was in the range of 5-7 pH, when filtered properly...

 

[Leebee]

wait, wait.
your RO/DI filter puts water out with pH at 9?
either your filter is broken or your test kit is wrong
i was under the impression that all RO/DI was in the range of 5-7 pH, when filtered properly...

Hi, no , my tap water is 9 (8.3 after 24 hours), kh is around 4/5, ro water is over 8 with bicarb added. RO with no bicarb is 9.5, but I don't think digital meters work real well on ro water.
RO/DI is brand new, tds is 0.

 

[vincenz]

Hello, welcome. I feel you can easily fix the diatom problem not by fooling around with your water, but just getting some otos when the tank is set up. They eat that stuff up, so if there's a constant supply of it...

 

[plantbrain]

Hi, no , my tap water is 9 (8.3 after 24 hours), kh is around 4/5, ro water is over 8 with bicarb added. RO with no bicarb is 9.5, but I don't think digital meters work real well on ro water.
RO/DI is brand new, tds is 0.

Sounds like great tap, no need to do anything else to it.
Just use that. Do not add bicarb , leave the KH at 4-5 this is fine.

 

[Leebee]

What about the PH. My plan is to bring it down with co2.

 

[Leebee]

So, back to my original question, do I need to worry about a variation in PH when I do a water change?

 

[izabella87]

Use some water conditioner when using tap water. Dont make more 25% water changes. If its a new tank, add in a few caps of healthy bacteria. (all sold even at walmart hehe)

 

[Leebee]

Well, I just calibrated my PH meter with 7.00 buffer and now my tank is is showing 7.8, guess it's not so bad as I thought.