ph & Kh High and Calcium Low

[lisacanup]

I started a 90 gal tank with 100# live rock, 60#(2" bed) aragonite oolite with 20# agralive sand to seed it. I have a Little Giant pump with a sump/refugium with live sand & lr rubble and red grape calurpa (sp) also have pods already. I also have what I think is a Euro Reef RS80 protein skimmer. I've had the system running now for 2 weeks and did my last 25% water change last night. I have had the lights off untill this week and now I am starting to get brown diatoms/algea on the live rock. My lighting isn't the greatest at the moment with 2 - 36w half daylight/actinic and then 2 - 36 w actinic. I have another light but am waiting for the bulbs to come in 4 - 36w 10,000 daylight. My water parameters are as follows..

Ammonia 0; Nitrite < .05; Nitrate 0; phosphates 0; ph(high) 8.6; KH(high) 18(red sea test kit); Calcium 280

Is it possible because I have so much actinic lighting this is causing the diatom/algea?
How do I lower the PH and KH?
What do you think about the lighting?

Any info on my specific setup would be much appreciated!!

Thank You!

 

[MT79]

The diatoms are a very common part of cycling a new tank. Cutting the lighting period by half, or more, will aid in getting rid of them. As nutrients are consumed over the next few weeks, things should settle down. As far as PH, KH go, do you know how it got so high? Are you using any additives? If so what? What brand salt mix are you using and have you tested any fresh SW for KH, PH? Usually the safest way to decrease parameters is through PWC's, assuming the salt mix is "balanced".

 

[lisacanup]

Have no clue why it is so high. It has been since I started. I have my own RO filter into 2 33 gallon barrels. I haven't test that water but will right now. I did put in last week 1 capful of Purple up and 1 cap full of Kent Liquid Calcium Supplement. I will repost after I test the RO water. Oh I am using Instant Ocean Salt.

 

[melosu58]

If you are in the middle of your cycle then you will get all kind of weird readings. Let your tank cycle and then do a 35% PWC and then let`s see what we have as far as alk and calcium. As Mike said PWC`s are the best way to get things back on track. I`m going to move this to the Start up forum.

 

[MT79]

IO salt Alk usually runs about 3.5 meg/l or 9.8 dkh. That should not be the problem, unless possibly you got a bad batch of salt. A test of some new, well mixed saltwater will tell for sure. I would advise against using any additives right now. Unless you are testing the levels of what your adding, it's better to not do anything. Regualr PWC's as part of your maintenance will provide/replenish the trace elements, minerals, etc.
Does your test kit have a reference test? Can you compare it to another kits results? Alk that high and Ca so low does not add up for IO salt. I think there may be an issue w/ the testing.

 

[lisacanup]

I tested my premixed saltwater and the test were the same as the tank ph 8.6 and alk 18 I have both Red Sea and API Test Kits and they both said the same. I also have Salifert Clacium test and they were both basically the same. I also tested my RO water w/o salt and the alk was still the same but the ph was lower 8.2 My well water before going through the RO Filter is alk high and ph 7.4. Also I never got a spike in ammonia it only went to .25 and now has stayed at zero for the last 4 days. How much longer and what am I looking for to know the cycling is over?

 

[MT79]

I also tested my RO water w/o salt and the alk was still the same but the ph was lower 8.2

Something is not right. There is no way RO water should have Alk that high, if any, and deifinitely not 8.2 PH. Going through an RO unit will lower PH. The PH of RO water is ~5-7. There is no way, that I know of at least, PH could be higher after going through the RO unit. I suspect user error. I would recommend taking a tank water sample to a LFS and asking them if they would verify your results.

Also I never got a spike in ammonia it only went to .25 and now has stayed at zero for the last 4 days. How much longer and what am I looking for to know the cycling is over?

If you used LR that was not out of water for a long period of time and did not introduce a source of ammonia, most likely there will not be enough die-off to see a cycle. If ammonia has risen and fallen, I would wait until nitrite is 0, and then slowly start adding fish. Slowly being the key word.
BTW, welcome to AA.com!

 

[Kurt_Nelson]

What salinity are you mixing your saltwater to? Are you testing using a swing arm hydrometer, or a refractometer?

As others have noted, there's no point in dosing anything in your tank at this point - you're just going to be doing some good sized water changes after the cycle and it's all going to go down the drain anyway.