PArameters off the chart with corals doing fine!

[maroun.c]

Can anyone please explain this:
A friends tank breaks a back pannel and has to be refilled and restarted. All LR corals and fish are kept in tank so basically expected cycle was a mild one. replaced his corals and started with no losses excpet a few while corals were in holding tanks (bathtub actually)
He orders 300 G of RO water from LFS and fills up the tank using RC. does a couple of water changes in teh weeks following the move and starts testing didn't test before as he was in a mess.
he discovers the follwing:

Alk in tank water around 18
Alk in fresh mixed water 28
I test Ro water that LFS is providing him and it's close to 300 in TDS which is causing the high alk levels as our water is very alkaline.
PO4 2

All testing performed by him then his wife (pharmacist) then me (trained on much more complex radioachemical purity testing) we use 3 different salifert test kits one JBL and another waterlife testkits with very close results.
I presume his phophates levels are from the water with high TDS or maybe from a small cycle he got?

since then he started doing waterchanges with good RO water and RC (alk around 10-11) so his levels dropped and are now at about 12 (very small tank demand)
in adidition to softies and LPS he's got:

Montipora
couple of accros

and I gave him (before finding out about alk and phophates) the follwing frags:

Millepora 2
hydnopora 2
montipora 3
accropora 2
scroll 2

All of this have survived and show much better PE than in my tank and are coloring up very well in his tank. to add to that there isn't a singl alga spot inhis tank did get a small brown alga on the sand buldup for 1 week after he restarted the tank but it went alone.
Same MH (14 K arcadia 150 W x4 in his tank) than in my tank which has 2 instead of 4 being shorter but I ahve a 3rd 250W ieseman bulb 22K and an additional 2 x 54 W actinic T5 with individual reflectors and 1 80 W 14 K T5.
Thanks for any explanation of this as it's defying all the rules of reefkeeping.
To add to that he only had a return pump and a single 1000G powerhead inteh tank and just added few streams to increase circulation.
sorry for the long post but had to give all the parameters.

 

[Randy Holmes-Farley]

300 ppm TDS water isn't RO water, IMO, unless the starting water is really salty.

That said, I'm not sure exactly what anomaly you want to discuss in more detail?

 

[maroun.c]

I beilve they just sold him regular water or had a really bad RO unit...
But I can't understand how the corals thrive through all this and the absecence of hair alga in his tank?

 

[Randy Holmes-Farley]

I would not assume that just because tap water was used,that it necessarily added a lot of nitrate or phosphate.

 

[maroun.c]

Could be because of his tank cycled or also because he's overstocked with fish without a growing fuge and without a snad bed and a modest skimmer for a tank his size...
but what I'm asking about is how can a full aquarium (fish inverts corals) thrive and frags from my tank do better in his tank than mother colonies in my tank with these values that persisted for at least 2 months???