finding an acros sweet spot

[Obmas]

hey, im new to this here forum and hoping everyone here can help me out. I have a 90g tank with 26 3watt crees with 50 degree optics (half cool white, half royal blue) and 2 t5 ho bulbs (ATI aqua blue and purple plus). I also have 2 mp40s on reef crest mode.
Im still trying to figure out where to place acros in my tank so they can thrive and grow well. I have a few small frags, some are doing much better than others though dispite being in simular light and flow areas. How can i know if they will like a spot long term when they never seem to be very happy where i put them?
thank you for any help

[consumed corals]

a good sign of thier happiness is when you see really good polyp extension

[allsps40]

Should be able to place SPS every where in the tank with lighting like that. I have 250w MH but I can place sps any where in the tank and know they will do just fine.

[Obmas]

i guess i havent really seen much polyp extension, even on the milli, thats why i ask. Are there any early signs i could use to adjust them?

[fishguy597]

What are your water parameters? how long has the tank been running?

[Obmas]

tank has been set up for about 8 months
last time i tested which was yesterday:
calcium- 460
alk- 7
ammonia, nitrite, and nitrate; all 0
ph 8.2
sg 1.025
mg 1200

[dirtyBit]

Alk and Mag seem a little low. I would up those a bit (SLOWLY). You seem to have adequate flow. Some corals don't liked to be moved and it may take some time before they adjust to the new spot.

[Obmas]

i have been working on bringing up my alk for a while now, i dose over 3 times as much alk as i do calcium. ill just wait and hope than i guess. i have only seen one ever extend its polyps and it was a maricultured one at night

[olee]

milli should place in high flow spot and the polyp will be good

[dave540]

i have been working on bringing up my alk for a while now, i dose over 3 times as much alk as i do calcium. ill just wait and hope than i guess. i have only seen one ever extend its polyps and it was a maricultured one at night

Your mag should be 3x what your cal is. So your mag should be closer to 1400. That should make it easier for you to raise your alk.

[Obmas]

Thanks you, for the milli can it have too much flow?
I'll also work on getting the mg up, I didn't realise it could affect it that much.

[ek9vboi]

Thanks you, for the milli can it have too much flow?
I'll also work on getting the mg up, I didn't realise it could affect it that much.

Millis love flow, just not direct.

Mag is very important when it comes to keeping alk and calcium levels in check. I would work on that first, you should take your mag levels up max of 100ppm a day. Check your powerheads or anything that might produce heat for precipitation since your dosing so much more of alk compared to calcium. If you don't have a test kit, considering buying a Salifert version. Same with the Calcium and Alkalinity if you haven't. These three are the more important test kits when it comes to testing. My mag is around 1500 and I have no problem keeping calc @440 and alk @9.

[Obmas]

Ill get a mg one tonight, I have all and calcium tests. Ill also get some mg supplement.